Show that for any $q$ in the interval $(1,2)$ exists $n$ to let the inequality of $m$ does not have positive...












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Show that $forall q in (1,2)$, $exists n in N^+$ let there is no $m in N^+$ satisfy the inequality$$q^n-q^{n-1}+1 le q^mlt q^{n+1}-q^n+1$$



The inequality can be written as $$q^{n-1}lefrac{q^m-1}{q-1}lt q^n$$



The sum of the geometric sequence is bigger than the $n-1$th term and the $n$th



term of a geometric sequence with a common ratio of $q$.



But I don't know what I can do next.



I am not sure whether the statement is correct.










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    0












    $begingroup$


    Show that $forall q in (1,2)$, $exists n in N^+$ let there is no $m in N^+$ satisfy the inequality$$q^n-q^{n-1}+1 le q^mlt q^{n+1}-q^n+1$$



    The inequality can be written as $$q^{n-1}lefrac{q^m-1}{q-1}lt q^n$$



    The sum of the geometric sequence is bigger than the $n-1$th term and the $n$th



    term of a geometric sequence with a common ratio of $q$.



    But I don't know what I can do next.



    I am not sure whether the statement is correct.










    share|cite|improve this question











    $endgroup$















      0












      0








      0





      $begingroup$


      Show that $forall q in (1,2)$, $exists n in N^+$ let there is no $m in N^+$ satisfy the inequality$$q^n-q^{n-1}+1 le q^mlt q^{n+1}-q^n+1$$



      The inequality can be written as $$q^{n-1}lefrac{q^m-1}{q-1}lt q^n$$



      The sum of the geometric sequence is bigger than the $n-1$th term and the $n$th



      term of a geometric sequence with a common ratio of $q$.



      But I don't know what I can do next.



      I am not sure whether the statement is correct.










      share|cite|improve this question











      $endgroup$




      Show that $forall q in (1,2)$, $exists n in N^+$ let there is no $m in N^+$ satisfy the inequality$$q^n-q^{n-1}+1 le q^mlt q^{n+1}-q^n+1$$



      The inequality can be written as $$q^{n-1}lefrac{q^m-1}{q-1}lt q^n$$



      The sum of the geometric sequence is bigger than the $n-1$th term and the $n$th



      term of a geometric sequence with a common ratio of $q$.



      But I don't know what I can do next.



      I am not sure whether the statement is correct.







      inequality






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      share|cite|improve this question













      share|cite|improve this question




      share|cite|improve this question








      edited Jan 7 at 13:31







      yuanming luo

















      asked Jan 6 at 3:40









      yuanming luoyuanming luo

      777




      777






















          3 Answers
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          0












          $begingroup$

          Consider fixed arbitrary $q in (1,2)$. Consider $q^i(2-q)$ as $i$ varies. This diverges to infinity, so in particular is eventually $geq 1$. Also $q^0(2-q)=2-q<1$. Thus there exists a smallest integer $k$ with $q^k(2-q) geq 1$, and we have $k geq 1$. By minimality of $k$ we get $q^{k-1}(2-q)<1$.



          Take $n=k in mathbb{N}^{+}$. We get
          $$q^{k-1}=q^{k-1}(q-1)+q^{k-1}(2-q)<q^{k-1}(q-1)+1=q^k-q^{k-1}+1$$
          $$q^k=q^k(q-1)+q^k(2-q) geq q^k(q-1)+1=q^{k+1}-q^k+1$$
          We are thus done, as $q^k-q^{k-1}+1 leq q^m<q^{k+1}-q^k+1$ then implies $k-1<m<k$, a contradiction, so no such $m$ exists.



          Remark: In fact it is possible to show that $q(2-q)<1$ for $qin (1,2)$, thus $k geq 2$, which reconciles with the fact that $m=1$ always works when $n=1$.






          share|cite|improve this answer











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            0












            $begingroup$

            Let $epsilon_n in [0,1] forall n$ with $epsilon_{t+1}>epsilon_t$.



            We have that $q$ is expressible as $1+epsilon_1$. This leads to: $$1+epsilon_2-epsilon_3leq q^m < 1+epsilon_3 - epsilon_2$$
            This draws that the only possible integer solution is $0$, which isn't positive.






            share|cite|improve this answer









            $endgroup$













            • $begingroup$
              I do not understand why the unique integer solution is 0.
              $endgroup$
              – yuanming luo
              Jan 6 at 5:16










            • $begingroup$
              Two reasons. $$|epsilon_3-epsilon_2|<1$$ and $q^0=1$
              $endgroup$
              – Rhys Hughes
              Jan 6 at 6:05










            • $begingroup$
              I still cannot catch your point and your reason. Could you explain your method with more details?
              $endgroup$
              – yuanming luo
              Jan 7 at 13:27










            • $begingroup$
              I implied that $$(1+epsilon_1)^n=1+epsilon_2$$, and $$(1+epsilon_1)^{n+1}=1+epsilon_3$$ and then applied that to the original statement
              $endgroup$
              – Rhys Hughes
              Jan 7 at 15:25



















            0












            $begingroup$

            $q^n-q^{n-1}+1
            le q^m
            lt q^{n+1}-q^n+1
            $



            The right inequality
            implies $m le n$ because
            $q^{n+1}-q^n+1
            lt q^{n+1}
            $

            so $m < n+1$
            so $m le n$.



            The left inequality,
            in contrast,
            has many solutions.



            Write it as
            $q^{n-1}(q-1)+1
            le q^m
            $

            and let
            $q = 1+x$
            where
            $0 < x < 1$.
            It becomes
            $x(1+x)^{n-1}+1
            le (1+x)^m
            $
            .



            If $frac1{n} le x le frac1{n-1}$,
            then
            $(1+x)^{n-1}
            le (1+frac1{n-1})^{n-1}
            lt e
            $

            so the left side is less than
            $1+frac{e}{n-1}
            $
            .



            For the right side,
            $q^m
            =(1+x)^m
            ge 1+mx
            ge 1+frac{m}{n}
            $

            so the left inequality is true if
            $1+frac{e}{n-1}
            lt 1+frac{m}{n}
            $

            or
            $m > frac{en}{n-1}
            gt 5
            $

            if
            $n ge 2
            $
            .



            Therefore,
            for any $m > 5$ and $n > 2$
            we can find a $q$
            so that the left inequality holds.






            share|cite|improve this answer









            $endgroup$













            • $begingroup$
              actually, the question I ask is to show for all q in the interval there is always existing n to let no positive integer m satisfy the inequality. I will edit again the question to let it less confusing.
              $endgroup$
              – yuanming luo
              Jan 7 at 12:00












            • $begingroup$
              I have already tried to close this question. The question posted on this web is clearer than this. If you still have the interest in the question I asked. math.stackexchange.com/questions/3064930/…
              $endgroup$
              – yuanming luo
              Jan 7 at 12:06











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            3 Answers
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            3 Answers
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            0












            $begingroup$

            Consider fixed arbitrary $q in (1,2)$. Consider $q^i(2-q)$ as $i$ varies. This diverges to infinity, so in particular is eventually $geq 1$. Also $q^0(2-q)=2-q<1$. Thus there exists a smallest integer $k$ with $q^k(2-q) geq 1$, and we have $k geq 1$. By minimality of $k$ we get $q^{k-1}(2-q)<1$.



            Take $n=k in mathbb{N}^{+}$. We get
            $$q^{k-1}=q^{k-1}(q-1)+q^{k-1}(2-q)<q^{k-1}(q-1)+1=q^k-q^{k-1}+1$$
            $$q^k=q^k(q-1)+q^k(2-q) geq q^k(q-1)+1=q^{k+1}-q^k+1$$
            We are thus done, as $q^k-q^{k-1}+1 leq q^m<q^{k+1}-q^k+1$ then implies $k-1<m<k$, a contradiction, so no such $m$ exists.



            Remark: In fact it is possible to show that $q(2-q)<1$ for $qin (1,2)$, thus $k geq 2$, which reconciles with the fact that $m=1$ always works when $n=1$.






            share|cite|improve this answer











            $endgroup$


















              0












              $begingroup$

              Consider fixed arbitrary $q in (1,2)$. Consider $q^i(2-q)$ as $i$ varies. This diverges to infinity, so in particular is eventually $geq 1$. Also $q^0(2-q)=2-q<1$. Thus there exists a smallest integer $k$ with $q^k(2-q) geq 1$, and we have $k geq 1$. By minimality of $k$ we get $q^{k-1}(2-q)<1$.



              Take $n=k in mathbb{N}^{+}$. We get
              $$q^{k-1}=q^{k-1}(q-1)+q^{k-1}(2-q)<q^{k-1}(q-1)+1=q^k-q^{k-1}+1$$
              $$q^k=q^k(q-1)+q^k(2-q) geq q^k(q-1)+1=q^{k+1}-q^k+1$$
              We are thus done, as $q^k-q^{k-1}+1 leq q^m<q^{k+1}-q^k+1$ then implies $k-1<m<k$, a contradiction, so no such $m$ exists.



              Remark: In fact it is possible to show that $q(2-q)<1$ for $qin (1,2)$, thus $k geq 2$, which reconciles with the fact that $m=1$ always works when $n=1$.






              share|cite|improve this answer











              $endgroup$
















                0












                0








                0





                $begingroup$

                Consider fixed arbitrary $q in (1,2)$. Consider $q^i(2-q)$ as $i$ varies. This diverges to infinity, so in particular is eventually $geq 1$. Also $q^0(2-q)=2-q<1$. Thus there exists a smallest integer $k$ with $q^k(2-q) geq 1$, and we have $k geq 1$. By minimality of $k$ we get $q^{k-1}(2-q)<1$.



                Take $n=k in mathbb{N}^{+}$. We get
                $$q^{k-1}=q^{k-1}(q-1)+q^{k-1}(2-q)<q^{k-1}(q-1)+1=q^k-q^{k-1}+1$$
                $$q^k=q^k(q-1)+q^k(2-q) geq q^k(q-1)+1=q^{k+1}-q^k+1$$
                We are thus done, as $q^k-q^{k-1}+1 leq q^m<q^{k+1}-q^k+1$ then implies $k-1<m<k$, a contradiction, so no such $m$ exists.



                Remark: In fact it is possible to show that $q(2-q)<1$ for $qin (1,2)$, thus $k geq 2$, which reconciles with the fact that $m=1$ always works when $n=1$.






                share|cite|improve this answer











                $endgroup$



                Consider fixed arbitrary $q in (1,2)$. Consider $q^i(2-q)$ as $i$ varies. This diverges to infinity, so in particular is eventually $geq 1$. Also $q^0(2-q)=2-q<1$. Thus there exists a smallest integer $k$ with $q^k(2-q) geq 1$, and we have $k geq 1$. By minimality of $k$ we get $q^{k-1}(2-q)<1$.



                Take $n=k in mathbb{N}^{+}$. We get
                $$q^{k-1}=q^{k-1}(q-1)+q^{k-1}(2-q)<q^{k-1}(q-1)+1=q^k-q^{k-1}+1$$
                $$q^k=q^k(q-1)+q^k(2-q) geq q^k(q-1)+1=q^{k+1}-q^k+1$$
                We are thus done, as $q^k-q^{k-1}+1 leq q^m<q^{k+1}-q^k+1$ then implies $k-1<m<k$, a contradiction, so no such $m$ exists.



                Remark: In fact it is possible to show that $q(2-q)<1$ for $qin (1,2)$, thus $k geq 2$, which reconciles with the fact that $m=1$ always works when $n=1$.







                share|cite|improve this answer














                share|cite|improve this answer



                share|cite|improve this answer








                edited Jan 7 at 14:16

























                answered Jan 7 at 14:03









                user632469user632469

                161




                161























                    0












                    $begingroup$

                    Let $epsilon_n in [0,1] forall n$ with $epsilon_{t+1}>epsilon_t$.



                    We have that $q$ is expressible as $1+epsilon_1$. This leads to: $$1+epsilon_2-epsilon_3leq q^m < 1+epsilon_3 - epsilon_2$$
                    This draws that the only possible integer solution is $0$, which isn't positive.






                    share|cite|improve this answer









                    $endgroup$













                    • $begingroup$
                      I do not understand why the unique integer solution is 0.
                      $endgroup$
                      – yuanming luo
                      Jan 6 at 5:16










                    • $begingroup$
                      Two reasons. $$|epsilon_3-epsilon_2|<1$$ and $q^0=1$
                      $endgroup$
                      – Rhys Hughes
                      Jan 6 at 6:05










                    • $begingroup$
                      I still cannot catch your point and your reason. Could you explain your method with more details?
                      $endgroup$
                      – yuanming luo
                      Jan 7 at 13:27










                    • $begingroup$
                      I implied that $$(1+epsilon_1)^n=1+epsilon_2$$, and $$(1+epsilon_1)^{n+1}=1+epsilon_3$$ and then applied that to the original statement
                      $endgroup$
                      – Rhys Hughes
                      Jan 7 at 15:25
















                    0












                    $begingroup$

                    Let $epsilon_n in [0,1] forall n$ with $epsilon_{t+1}>epsilon_t$.



                    We have that $q$ is expressible as $1+epsilon_1$. This leads to: $$1+epsilon_2-epsilon_3leq q^m < 1+epsilon_3 - epsilon_2$$
                    This draws that the only possible integer solution is $0$, which isn't positive.






                    share|cite|improve this answer









                    $endgroup$













                    • $begingroup$
                      I do not understand why the unique integer solution is 0.
                      $endgroup$
                      – yuanming luo
                      Jan 6 at 5:16










                    • $begingroup$
                      Two reasons. $$|epsilon_3-epsilon_2|<1$$ and $q^0=1$
                      $endgroup$
                      – Rhys Hughes
                      Jan 6 at 6:05










                    • $begingroup$
                      I still cannot catch your point and your reason. Could you explain your method with more details?
                      $endgroup$
                      – yuanming luo
                      Jan 7 at 13:27










                    • $begingroup$
                      I implied that $$(1+epsilon_1)^n=1+epsilon_2$$, and $$(1+epsilon_1)^{n+1}=1+epsilon_3$$ and then applied that to the original statement
                      $endgroup$
                      – Rhys Hughes
                      Jan 7 at 15:25














                    0












                    0








                    0





                    $begingroup$

                    Let $epsilon_n in [0,1] forall n$ with $epsilon_{t+1}>epsilon_t$.



                    We have that $q$ is expressible as $1+epsilon_1$. This leads to: $$1+epsilon_2-epsilon_3leq q^m < 1+epsilon_3 - epsilon_2$$
                    This draws that the only possible integer solution is $0$, which isn't positive.






                    share|cite|improve this answer









                    $endgroup$



                    Let $epsilon_n in [0,1] forall n$ with $epsilon_{t+1}>epsilon_t$.



                    We have that $q$ is expressible as $1+epsilon_1$. This leads to: $$1+epsilon_2-epsilon_3leq q^m < 1+epsilon_3 - epsilon_2$$
                    This draws that the only possible integer solution is $0$, which isn't positive.







                    share|cite|improve this answer












                    share|cite|improve this answer



                    share|cite|improve this answer










                    answered Jan 6 at 4:51









                    Rhys HughesRhys Hughes

                    6,0171530




                    6,0171530












                    • $begingroup$
                      I do not understand why the unique integer solution is 0.
                      $endgroup$
                      – yuanming luo
                      Jan 6 at 5:16










                    • $begingroup$
                      Two reasons. $$|epsilon_3-epsilon_2|<1$$ and $q^0=1$
                      $endgroup$
                      – Rhys Hughes
                      Jan 6 at 6:05










                    • $begingroup$
                      I still cannot catch your point and your reason. Could you explain your method with more details?
                      $endgroup$
                      – yuanming luo
                      Jan 7 at 13:27










                    • $begingroup$
                      I implied that $$(1+epsilon_1)^n=1+epsilon_2$$, and $$(1+epsilon_1)^{n+1}=1+epsilon_3$$ and then applied that to the original statement
                      $endgroup$
                      – Rhys Hughes
                      Jan 7 at 15:25


















                    • $begingroup$
                      I do not understand why the unique integer solution is 0.
                      $endgroup$
                      – yuanming luo
                      Jan 6 at 5:16










                    • $begingroup$
                      Two reasons. $$|epsilon_3-epsilon_2|<1$$ and $q^0=1$
                      $endgroup$
                      – Rhys Hughes
                      Jan 6 at 6:05










                    • $begingroup$
                      I still cannot catch your point and your reason. Could you explain your method with more details?
                      $endgroup$
                      – yuanming luo
                      Jan 7 at 13:27










                    • $begingroup$
                      I implied that $$(1+epsilon_1)^n=1+epsilon_2$$, and $$(1+epsilon_1)^{n+1}=1+epsilon_3$$ and then applied that to the original statement
                      $endgroup$
                      – Rhys Hughes
                      Jan 7 at 15:25
















                    $begingroup$
                    I do not understand why the unique integer solution is 0.
                    $endgroup$
                    – yuanming luo
                    Jan 6 at 5:16




                    $begingroup$
                    I do not understand why the unique integer solution is 0.
                    $endgroup$
                    – yuanming luo
                    Jan 6 at 5:16












                    $begingroup$
                    Two reasons. $$|epsilon_3-epsilon_2|<1$$ and $q^0=1$
                    $endgroup$
                    – Rhys Hughes
                    Jan 6 at 6:05




                    $begingroup$
                    Two reasons. $$|epsilon_3-epsilon_2|<1$$ and $q^0=1$
                    $endgroup$
                    – Rhys Hughes
                    Jan 6 at 6:05












                    $begingroup$
                    I still cannot catch your point and your reason. Could you explain your method with more details?
                    $endgroup$
                    – yuanming luo
                    Jan 7 at 13:27




                    $begingroup$
                    I still cannot catch your point and your reason. Could you explain your method with more details?
                    $endgroup$
                    – yuanming luo
                    Jan 7 at 13:27












                    $begingroup$
                    I implied that $$(1+epsilon_1)^n=1+epsilon_2$$, and $$(1+epsilon_1)^{n+1}=1+epsilon_3$$ and then applied that to the original statement
                    $endgroup$
                    – Rhys Hughes
                    Jan 7 at 15:25




                    $begingroup$
                    I implied that $$(1+epsilon_1)^n=1+epsilon_2$$, and $$(1+epsilon_1)^{n+1}=1+epsilon_3$$ and then applied that to the original statement
                    $endgroup$
                    – Rhys Hughes
                    Jan 7 at 15:25











                    0












                    $begingroup$

                    $q^n-q^{n-1}+1
                    le q^m
                    lt q^{n+1}-q^n+1
                    $



                    The right inequality
                    implies $m le n$ because
                    $q^{n+1}-q^n+1
                    lt q^{n+1}
                    $

                    so $m < n+1$
                    so $m le n$.



                    The left inequality,
                    in contrast,
                    has many solutions.



                    Write it as
                    $q^{n-1}(q-1)+1
                    le q^m
                    $

                    and let
                    $q = 1+x$
                    where
                    $0 < x < 1$.
                    It becomes
                    $x(1+x)^{n-1}+1
                    le (1+x)^m
                    $
                    .



                    If $frac1{n} le x le frac1{n-1}$,
                    then
                    $(1+x)^{n-1}
                    le (1+frac1{n-1})^{n-1}
                    lt e
                    $

                    so the left side is less than
                    $1+frac{e}{n-1}
                    $
                    .



                    For the right side,
                    $q^m
                    =(1+x)^m
                    ge 1+mx
                    ge 1+frac{m}{n}
                    $

                    so the left inequality is true if
                    $1+frac{e}{n-1}
                    lt 1+frac{m}{n}
                    $

                    or
                    $m > frac{en}{n-1}
                    gt 5
                    $

                    if
                    $n ge 2
                    $
                    .



                    Therefore,
                    for any $m > 5$ and $n > 2$
                    we can find a $q$
                    so that the left inequality holds.






                    share|cite|improve this answer









                    $endgroup$













                    • $begingroup$
                      actually, the question I ask is to show for all q in the interval there is always existing n to let no positive integer m satisfy the inequality. I will edit again the question to let it less confusing.
                      $endgroup$
                      – yuanming luo
                      Jan 7 at 12:00












                    • $begingroup$
                      I have already tried to close this question. The question posted on this web is clearer than this. If you still have the interest in the question I asked. math.stackexchange.com/questions/3064930/…
                      $endgroup$
                      – yuanming luo
                      Jan 7 at 12:06
















                    0












                    $begingroup$

                    $q^n-q^{n-1}+1
                    le q^m
                    lt q^{n+1}-q^n+1
                    $



                    The right inequality
                    implies $m le n$ because
                    $q^{n+1}-q^n+1
                    lt q^{n+1}
                    $

                    so $m < n+1$
                    so $m le n$.



                    The left inequality,
                    in contrast,
                    has many solutions.



                    Write it as
                    $q^{n-1}(q-1)+1
                    le q^m
                    $

                    and let
                    $q = 1+x$
                    where
                    $0 < x < 1$.
                    It becomes
                    $x(1+x)^{n-1}+1
                    le (1+x)^m
                    $
                    .



                    If $frac1{n} le x le frac1{n-1}$,
                    then
                    $(1+x)^{n-1}
                    le (1+frac1{n-1})^{n-1}
                    lt e
                    $

                    so the left side is less than
                    $1+frac{e}{n-1}
                    $
                    .



                    For the right side,
                    $q^m
                    =(1+x)^m
                    ge 1+mx
                    ge 1+frac{m}{n}
                    $

                    so the left inequality is true if
                    $1+frac{e}{n-1}
                    lt 1+frac{m}{n}
                    $

                    or
                    $m > frac{en}{n-1}
                    gt 5
                    $

                    if
                    $n ge 2
                    $
                    .



                    Therefore,
                    for any $m > 5$ and $n > 2$
                    we can find a $q$
                    so that the left inequality holds.






                    share|cite|improve this answer









                    $endgroup$













                    • $begingroup$
                      actually, the question I ask is to show for all q in the interval there is always existing n to let no positive integer m satisfy the inequality. I will edit again the question to let it less confusing.
                      $endgroup$
                      – yuanming luo
                      Jan 7 at 12:00












                    • $begingroup$
                      I have already tried to close this question. The question posted on this web is clearer than this. If you still have the interest in the question I asked. math.stackexchange.com/questions/3064930/…
                      $endgroup$
                      – yuanming luo
                      Jan 7 at 12:06














                    0












                    0








                    0





                    $begingroup$

                    $q^n-q^{n-1}+1
                    le q^m
                    lt q^{n+1}-q^n+1
                    $



                    The right inequality
                    implies $m le n$ because
                    $q^{n+1}-q^n+1
                    lt q^{n+1}
                    $

                    so $m < n+1$
                    so $m le n$.



                    The left inequality,
                    in contrast,
                    has many solutions.



                    Write it as
                    $q^{n-1}(q-1)+1
                    le q^m
                    $

                    and let
                    $q = 1+x$
                    where
                    $0 < x < 1$.
                    It becomes
                    $x(1+x)^{n-1}+1
                    le (1+x)^m
                    $
                    .



                    If $frac1{n} le x le frac1{n-1}$,
                    then
                    $(1+x)^{n-1}
                    le (1+frac1{n-1})^{n-1}
                    lt e
                    $

                    so the left side is less than
                    $1+frac{e}{n-1}
                    $
                    .



                    For the right side,
                    $q^m
                    =(1+x)^m
                    ge 1+mx
                    ge 1+frac{m}{n}
                    $

                    so the left inequality is true if
                    $1+frac{e}{n-1}
                    lt 1+frac{m}{n}
                    $

                    or
                    $m > frac{en}{n-1}
                    gt 5
                    $

                    if
                    $n ge 2
                    $
                    .



                    Therefore,
                    for any $m > 5$ and $n > 2$
                    we can find a $q$
                    so that the left inequality holds.






                    share|cite|improve this answer









                    $endgroup$



                    $q^n-q^{n-1}+1
                    le q^m
                    lt q^{n+1}-q^n+1
                    $



                    The right inequality
                    implies $m le n$ because
                    $q^{n+1}-q^n+1
                    lt q^{n+1}
                    $

                    so $m < n+1$
                    so $m le n$.



                    The left inequality,
                    in contrast,
                    has many solutions.



                    Write it as
                    $q^{n-1}(q-1)+1
                    le q^m
                    $

                    and let
                    $q = 1+x$
                    where
                    $0 < x < 1$.
                    It becomes
                    $x(1+x)^{n-1}+1
                    le (1+x)^m
                    $
                    .



                    If $frac1{n} le x le frac1{n-1}$,
                    then
                    $(1+x)^{n-1}
                    le (1+frac1{n-1})^{n-1}
                    lt e
                    $

                    so the left side is less than
                    $1+frac{e}{n-1}
                    $
                    .



                    For the right side,
                    $q^m
                    =(1+x)^m
                    ge 1+mx
                    ge 1+frac{m}{n}
                    $

                    so the left inequality is true if
                    $1+frac{e}{n-1}
                    lt 1+frac{m}{n}
                    $

                    or
                    $m > frac{en}{n-1}
                    gt 5
                    $

                    if
                    $n ge 2
                    $
                    .



                    Therefore,
                    for any $m > 5$ and $n > 2$
                    we can find a $q$
                    so that the left inequality holds.







                    share|cite|improve this answer












                    share|cite|improve this answer



                    share|cite|improve this answer










                    answered Jan 7 at 1:41









                    marty cohenmarty cohen

                    73.3k549128




                    73.3k549128












                    • $begingroup$
                      actually, the question I ask is to show for all q in the interval there is always existing n to let no positive integer m satisfy the inequality. I will edit again the question to let it less confusing.
                      $endgroup$
                      – yuanming luo
                      Jan 7 at 12:00












                    • $begingroup$
                      I have already tried to close this question. The question posted on this web is clearer than this. If you still have the interest in the question I asked. math.stackexchange.com/questions/3064930/…
                      $endgroup$
                      – yuanming luo
                      Jan 7 at 12:06


















                    • $begingroup$
                      actually, the question I ask is to show for all q in the interval there is always existing n to let no positive integer m satisfy the inequality. I will edit again the question to let it less confusing.
                      $endgroup$
                      – yuanming luo
                      Jan 7 at 12:00












                    • $begingroup$
                      I have already tried to close this question. The question posted on this web is clearer than this. If you still have the interest in the question I asked. math.stackexchange.com/questions/3064930/…
                      $endgroup$
                      – yuanming luo
                      Jan 7 at 12:06
















                    $begingroup$
                    actually, the question I ask is to show for all q in the interval there is always existing n to let no positive integer m satisfy the inequality. I will edit again the question to let it less confusing.
                    $endgroup$
                    – yuanming luo
                    Jan 7 at 12:00






                    $begingroup$
                    actually, the question I ask is to show for all q in the interval there is always existing n to let no positive integer m satisfy the inequality. I will edit again the question to let it less confusing.
                    $endgroup$
                    – yuanming luo
                    Jan 7 at 12:00














                    $begingroup$
                    I have already tried to close this question. The question posted on this web is clearer than this. If you still have the interest in the question I asked. math.stackexchange.com/questions/3064930/…
                    $endgroup$
                    – yuanming luo
                    Jan 7 at 12:06




                    $begingroup$
                    I have already tried to close this question. The question posted on this web is clearer than this. If you still have the interest in the question I asked. math.stackexchange.com/questions/3064930/…
                    $endgroup$
                    – yuanming luo
                    Jan 7 at 12:06


















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