Find the x intercepts of $f(x)=tanleft(xright)-tanleft(4xright)$












0












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I'm having serious trouble finding the x-intercepts of this funtion $$f(x)=tan(x)-tan(4x)$$ I'm unable to solve it for zero. What am I missing here?






functions trigonometry







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    0












    $begingroup$


    I'm having serious trouble finding the x-intercepts of this funtion $$f(x)=tan(x)-tan(4x)$$ I'm unable to solve it for zero. What am I missing here?






    functions trigonometry







    share|cite|improve this question











    $endgroup$















      0












      0








      0





      $begingroup$


      I'm having serious trouble finding the x-intercepts of this funtion $$f(x)=tan(x)-tan(4x)$$ I'm unable to solve it for zero. What am I missing here?






      functions trigonometry







      share|cite|improve this question











      $endgroup$




      I'm having serious trouble finding the x-intercepts of this funtion $$f(x)=tan(x)-tan(4x)$$ I'm unable to solve it for zero. What am I missing here?






      functions trigonometry




      functions trigonometry






      share|cite|improve this question















      share|cite|improve this question













      share|cite|improve this question




      share|cite|improve this question








      edited Jan 18 at 15:46









      Blue

      48.6k870156




      48.6k870156










      asked Jan 18 at 15:28









      Daniel OscarDaniel Oscar

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          2 Answers
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          $begingroup$

          Hint



          $$tan a =tan biff a=kpi +b$$






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            2












            $begingroup$

            Simplify:
            $$fleft(xright)=tanleft(xright)-tanleft(4xright)=frac{sin xcos 4x-sin 4xcos x}{cos xcos 4x}=cdots$$






            share|cite|improve this answer









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            • $begingroup$
              Wait! Your first comment was it! I wasn't familiarized with that trigonometric identity!
              $endgroup$
              – Daniel Oscar
              Jan 18 at 15:48











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            2 Answers
            2






            active

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            2 Answers
            2






            active

            oldest

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            active

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            active

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            4












            $begingroup$

            Hint



            $$tan a =tan biff a=kpi +b$$






            share|cite|improve this answer









            $endgroup$


















              4












              $begingroup$

              Hint



              $$tan a =tan biff a=kpi +b$$






              share|cite|improve this answer









              $endgroup$
















                4












                4








                4





                $begingroup$

                Hint



                $$tan a =tan biff a=kpi +b$$






                share|cite|improve this answer









                $endgroup$



                Hint



                $$tan a =tan biff a=kpi +b$$







                share|cite|improve this answer












                share|cite|improve this answer



                share|cite|improve this answer










                answered Jan 18 at 15:38









                Mostafa AyazMostafa Ayaz

                15.6k3939




                15.6k3939























                    2












                    $begingroup$

                    Simplify:
                    $$fleft(xright)=tanleft(xright)-tanleft(4xright)=frac{sin xcos 4x-sin 4xcos x}{cos xcos 4x}=cdots$$






                    share|cite|improve this answer









                    $endgroup$













                    • $begingroup$
                      Wait! Your first comment was it! I wasn't familiarized with that trigonometric identity!
                      $endgroup$
                      – Daniel Oscar
                      Jan 18 at 15:48
















                    2












                    $begingroup$

                    Simplify:
                    $$fleft(xright)=tanleft(xright)-tanleft(4xright)=frac{sin xcos 4x-sin 4xcos x}{cos xcos 4x}=cdots$$






                    share|cite|improve this answer









                    $endgroup$













                    • $begingroup$
                      Wait! Your first comment was it! I wasn't familiarized with that trigonometric identity!
                      $endgroup$
                      – Daniel Oscar
                      Jan 18 at 15:48














                    2












                    2








                    2





                    $begingroup$

                    Simplify:
                    $$fleft(xright)=tanleft(xright)-tanleft(4xright)=frac{sin xcos 4x-sin 4xcos x}{cos xcos 4x}=cdots$$






                    share|cite|improve this answer









                    $endgroup$



                    Simplify:
                    $$fleft(xright)=tanleft(xright)-tanleft(4xright)=frac{sin xcos 4x-sin 4xcos x}{cos xcos 4x}=cdots$$







                    share|cite|improve this answer












                    share|cite|improve this answer



                    share|cite|improve this answer










                    answered Jan 18 at 15:41









                    farruhotafarruhota

                    20.5k2739




                    20.5k2739












                    • $begingroup$
                      Wait! Your first comment was it! I wasn't familiarized with that trigonometric identity!
                      $endgroup$
                      – Daniel Oscar
                      Jan 18 at 15:48


















                    • $begingroup$
                      Wait! Your first comment was it! I wasn't familiarized with that trigonometric identity!
                      $endgroup$
                      – Daniel Oscar
                      Jan 18 at 15:48
















                    $begingroup$
                    Wait! Your first comment was it! I wasn't familiarized with that trigonometric identity!
                    $endgroup$
                    – Daniel Oscar
                    Jan 18 at 15:48




                    $begingroup$
                    Wait! Your first comment was it! I wasn't familiarized with that trigonometric identity!
                    $endgroup$
                    – Daniel Oscar
                    Jan 18 at 15:48


















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