How do i calculate $lim_{hto0}frac{f(a+h^2)-f(a+h)}{h}$?
$begingroup$
All do i know about this problem is that f can be derived in "a".
What troubles me is the h squared,i just can't get rid of it or make it useful,no matter what i do, i always end up with it giving me an undefined limit, so it stays like that,any idea on how to get rid of it? or any rule i can use to make this easy?
calculus limits derivatives
$endgroup$
add a comment |
$begingroup$
All do i know about this problem is that f can be derived in "a".
What troubles me is the h squared,i just can't get rid of it or make it useful,no matter what i do, i always end up with it giving me an undefined limit, so it stays like that,any idea on how to get rid of it? or any rule i can use to make this easy?
calculus limits derivatives
$endgroup$
add a comment |
$begingroup$
All do i know about this problem is that f can be derived in "a".
What troubles me is the h squared,i just can't get rid of it or make it useful,no matter what i do, i always end up with it giving me an undefined limit, so it stays like that,any idea on how to get rid of it? or any rule i can use to make this easy?
calculus limits derivatives
$endgroup$
All do i know about this problem is that f can be derived in "a".
What troubles me is the h squared,i just can't get rid of it or make it useful,no matter what i do, i always end up with it giving me an undefined limit, so it stays like that,any idea on how to get rid of it? or any rule i can use to make this easy?
calculus limits derivatives
calculus limits derivatives
edited Jan 31 at 21:51
Salah Gaming
asked Jan 31 at 21:48


Salah GamingSalah Gaming
293
293
add a comment |
add a comment |
3 Answers
3
active
oldest
votes
$begingroup$
You can write
$$frac{f(a + h^2) - f(a+h)}{h} = h cdot frac{f(a+h^2) - f(a)}{h^2} - frac{f(a+h) - f(a)}{h}$$
and compute these two limits individually.
$endgroup$
$begingroup$
yup worked,thanks a lot!
$endgroup$
– Salah Gaming
Jan 31 at 21:58
add a comment |
$begingroup$
This is
$$lim_{hto0}frac{f(a+h^2)-f(a)}{h}-lim_{hto0}frac{f(a+h)-f(a)}{h}.$$
If $f'(a)$ exists, this is
$$lim_{hto0}hleft(frac{f(a+h^2)-f(a)}{h^2}right)-f'(a)=-f'(a).$$
$endgroup$
add a comment |
$begingroup$
Hint:$$lim_{hto0}frac{f(a+h^2)-f(a)}h=lim_{hto0}hfrac{f(a+h^2)-f(a)}{h^2}=htimes f'(a)=0.$$
$endgroup$
$begingroup$
Can you explain why it would be kosher to say $lim h[K(h^2)] = lim h(lim K(w)) = lim h*f'(x) = 0$? Is it okay to split a limit that way.
$endgroup$
– fleablood
Jan 31 at 21:57
$begingroup$
Thanks btw u helped me a lot!
$endgroup$
– Salah Gaming
Jan 31 at 21:58
$begingroup$
I see you using "$fleft(a + h^2right) - fleft(aright)$" in the numerator compared to the question's "$fleft(a + h^2right) - fleft(a + hright)$" based on the value split, but you may wish to make this clear in your answer.
$endgroup$
– John Omielan
Jan 31 at 22:06
$begingroup$
@fleablood Yes, it is fine, as long as both limits exist.
$endgroup$
– José Carlos Santos
Jan 31 at 22:10
1
$begingroup$
No, my answer is not $0$. I did not provide an answer. I provided a hint to help the OP to obtain the answer.
$endgroup$
– José Carlos Santos
Jan 31 at 22:30
|
show 2 more comments
Your Answer
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3 Answers
3
active
oldest
votes
3 Answers
3
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
You can write
$$frac{f(a + h^2) - f(a+h)}{h} = h cdot frac{f(a+h^2) - f(a)}{h^2} - frac{f(a+h) - f(a)}{h}$$
and compute these two limits individually.
$endgroup$
$begingroup$
yup worked,thanks a lot!
$endgroup$
– Salah Gaming
Jan 31 at 21:58
add a comment |
$begingroup$
You can write
$$frac{f(a + h^2) - f(a+h)}{h} = h cdot frac{f(a+h^2) - f(a)}{h^2} - frac{f(a+h) - f(a)}{h}$$
and compute these two limits individually.
$endgroup$
$begingroup$
yup worked,thanks a lot!
$endgroup$
– Salah Gaming
Jan 31 at 21:58
add a comment |
$begingroup$
You can write
$$frac{f(a + h^2) - f(a+h)}{h} = h cdot frac{f(a+h^2) - f(a)}{h^2} - frac{f(a+h) - f(a)}{h}$$
and compute these two limits individually.
$endgroup$
You can write
$$frac{f(a + h^2) - f(a+h)}{h} = h cdot frac{f(a+h^2) - f(a)}{h^2} - frac{f(a+h) - f(a)}{h}$$
and compute these two limits individually.
answered Jan 31 at 21:52
Umberto P.Umberto P.
40.3k13370
40.3k13370
$begingroup$
yup worked,thanks a lot!
$endgroup$
– Salah Gaming
Jan 31 at 21:58
add a comment |
$begingroup$
yup worked,thanks a lot!
$endgroup$
– Salah Gaming
Jan 31 at 21:58
$begingroup$
yup worked,thanks a lot!
$endgroup$
– Salah Gaming
Jan 31 at 21:58
$begingroup$
yup worked,thanks a lot!
$endgroup$
– Salah Gaming
Jan 31 at 21:58
add a comment |
$begingroup$
This is
$$lim_{hto0}frac{f(a+h^2)-f(a)}{h}-lim_{hto0}frac{f(a+h)-f(a)}{h}.$$
If $f'(a)$ exists, this is
$$lim_{hto0}hleft(frac{f(a+h^2)-f(a)}{h^2}right)-f'(a)=-f'(a).$$
$endgroup$
add a comment |
$begingroup$
This is
$$lim_{hto0}frac{f(a+h^2)-f(a)}{h}-lim_{hto0}frac{f(a+h)-f(a)}{h}.$$
If $f'(a)$ exists, this is
$$lim_{hto0}hleft(frac{f(a+h^2)-f(a)}{h^2}right)-f'(a)=-f'(a).$$
$endgroup$
add a comment |
$begingroup$
This is
$$lim_{hto0}frac{f(a+h^2)-f(a)}{h}-lim_{hto0}frac{f(a+h)-f(a)}{h}.$$
If $f'(a)$ exists, this is
$$lim_{hto0}hleft(frac{f(a+h^2)-f(a)}{h^2}right)-f'(a)=-f'(a).$$
$endgroup$
This is
$$lim_{hto0}frac{f(a+h^2)-f(a)}{h}-lim_{hto0}frac{f(a+h)-f(a)}{h}.$$
If $f'(a)$ exists, this is
$$lim_{hto0}hleft(frac{f(a+h^2)-f(a)}{h^2}right)-f'(a)=-f'(a).$$
answered Jan 31 at 21:52
Lord Shark the UnknownLord Shark the Unknown
108k1162136
108k1162136
add a comment |
add a comment |
$begingroup$
Hint:$$lim_{hto0}frac{f(a+h^2)-f(a)}h=lim_{hto0}hfrac{f(a+h^2)-f(a)}{h^2}=htimes f'(a)=0.$$
$endgroup$
$begingroup$
Can you explain why it would be kosher to say $lim h[K(h^2)] = lim h(lim K(w)) = lim h*f'(x) = 0$? Is it okay to split a limit that way.
$endgroup$
– fleablood
Jan 31 at 21:57
$begingroup$
Thanks btw u helped me a lot!
$endgroup$
– Salah Gaming
Jan 31 at 21:58
$begingroup$
I see you using "$fleft(a + h^2right) - fleft(aright)$" in the numerator compared to the question's "$fleft(a + h^2right) - fleft(a + hright)$" based on the value split, but you may wish to make this clear in your answer.
$endgroup$
– John Omielan
Jan 31 at 22:06
$begingroup$
@fleablood Yes, it is fine, as long as both limits exist.
$endgroup$
– José Carlos Santos
Jan 31 at 22:10
1
$begingroup$
No, my answer is not $0$. I did not provide an answer. I provided a hint to help the OP to obtain the answer.
$endgroup$
– José Carlos Santos
Jan 31 at 22:30
|
show 2 more comments
$begingroup$
Hint:$$lim_{hto0}frac{f(a+h^2)-f(a)}h=lim_{hto0}hfrac{f(a+h^2)-f(a)}{h^2}=htimes f'(a)=0.$$
$endgroup$
$begingroup$
Can you explain why it would be kosher to say $lim h[K(h^2)] = lim h(lim K(w)) = lim h*f'(x) = 0$? Is it okay to split a limit that way.
$endgroup$
– fleablood
Jan 31 at 21:57
$begingroup$
Thanks btw u helped me a lot!
$endgroup$
– Salah Gaming
Jan 31 at 21:58
$begingroup$
I see you using "$fleft(a + h^2right) - fleft(aright)$" in the numerator compared to the question's "$fleft(a + h^2right) - fleft(a + hright)$" based on the value split, but you may wish to make this clear in your answer.
$endgroup$
– John Omielan
Jan 31 at 22:06
$begingroup$
@fleablood Yes, it is fine, as long as both limits exist.
$endgroup$
– José Carlos Santos
Jan 31 at 22:10
1
$begingroup$
No, my answer is not $0$. I did not provide an answer. I provided a hint to help the OP to obtain the answer.
$endgroup$
– José Carlos Santos
Jan 31 at 22:30
|
show 2 more comments
$begingroup$
Hint:$$lim_{hto0}frac{f(a+h^2)-f(a)}h=lim_{hto0}hfrac{f(a+h^2)-f(a)}{h^2}=htimes f'(a)=0.$$
$endgroup$
Hint:$$lim_{hto0}frac{f(a+h^2)-f(a)}h=lim_{hto0}hfrac{f(a+h^2)-f(a)}{h^2}=htimes f'(a)=0.$$
answered Jan 31 at 21:52


José Carlos SantosJosé Carlos Santos
173k23133241
173k23133241
$begingroup$
Can you explain why it would be kosher to say $lim h[K(h^2)] = lim h(lim K(w)) = lim h*f'(x) = 0$? Is it okay to split a limit that way.
$endgroup$
– fleablood
Jan 31 at 21:57
$begingroup$
Thanks btw u helped me a lot!
$endgroup$
– Salah Gaming
Jan 31 at 21:58
$begingroup$
I see you using "$fleft(a + h^2right) - fleft(aright)$" in the numerator compared to the question's "$fleft(a + h^2right) - fleft(a + hright)$" based on the value split, but you may wish to make this clear in your answer.
$endgroup$
– John Omielan
Jan 31 at 22:06
$begingroup$
@fleablood Yes, it is fine, as long as both limits exist.
$endgroup$
– José Carlos Santos
Jan 31 at 22:10
1
$begingroup$
No, my answer is not $0$. I did not provide an answer. I provided a hint to help the OP to obtain the answer.
$endgroup$
– José Carlos Santos
Jan 31 at 22:30
|
show 2 more comments
$begingroup$
Can you explain why it would be kosher to say $lim h[K(h^2)] = lim h(lim K(w)) = lim h*f'(x) = 0$? Is it okay to split a limit that way.
$endgroup$
– fleablood
Jan 31 at 21:57
$begingroup$
Thanks btw u helped me a lot!
$endgroup$
– Salah Gaming
Jan 31 at 21:58
$begingroup$
I see you using "$fleft(a + h^2right) - fleft(aright)$" in the numerator compared to the question's "$fleft(a + h^2right) - fleft(a + hright)$" based on the value split, but you may wish to make this clear in your answer.
$endgroup$
– John Omielan
Jan 31 at 22:06
$begingroup$
@fleablood Yes, it is fine, as long as both limits exist.
$endgroup$
– José Carlos Santos
Jan 31 at 22:10
1
$begingroup$
No, my answer is not $0$. I did not provide an answer. I provided a hint to help the OP to obtain the answer.
$endgroup$
– José Carlos Santos
Jan 31 at 22:30
$begingroup$
Can you explain why it would be kosher to say $lim h[K(h^2)] = lim h(lim K(w)) = lim h*f'(x) = 0$? Is it okay to split a limit that way.
$endgroup$
– fleablood
Jan 31 at 21:57
$begingroup$
Can you explain why it would be kosher to say $lim h[K(h^2)] = lim h(lim K(w)) = lim h*f'(x) = 0$? Is it okay to split a limit that way.
$endgroup$
– fleablood
Jan 31 at 21:57
$begingroup$
Thanks btw u helped me a lot!
$endgroup$
– Salah Gaming
Jan 31 at 21:58
$begingroup$
Thanks btw u helped me a lot!
$endgroup$
– Salah Gaming
Jan 31 at 21:58
$begingroup$
I see you using "$fleft(a + h^2right) - fleft(aright)$" in the numerator compared to the question's "$fleft(a + h^2right) - fleft(a + hright)$" based on the value split, but you may wish to make this clear in your answer.
$endgroup$
– John Omielan
Jan 31 at 22:06
$begingroup$
I see you using "$fleft(a + h^2right) - fleft(aright)$" in the numerator compared to the question's "$fleft(a + h^2right) - fleft(a + hright)$" based on the value split, but you may wish to make this clear in your answer.
$endgroup$
– John Omielan
Jan 31 at 22:06
$begingroup$
@fleablood Yes, it is fine, as long as both limits exist.
$endgroup$
– José Carlos Santos
Jan 31 at 22:10
$begingroup$
@fleablood Yes, it is fine, as long as both limits exist.
$endgroup$
– José Carlos Santos
Jan 31 at 22:10
1
1
$begingroup$
No, my answer is not $0$. I did not provide an answer. I provided a hint to help the OP to obtain the answer.
$endgroup$
– José Carlos Santos
Jan 31 at 22:30
$begingroup$
No, my answer is not $0$. I did not provide an answer. I provided a hint to help the OP to obtain the answer.
$endgroup$
– José Carlos Santos
Jan 31 at 22:30
|
show 2 more comments
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