Piece-wise function Differentiable?












2












$begingroup$


Consider the following function $f : Bbb R to Bbb R$:



$$f(x) = begin{cases} sin x & x ge 0 \ x^2 + e^x & x < 0 end{cases}$$



I was wondering if the above piece-wise function was differentiable over the set of Real numbers R, and how to figure it out.



I know that differentiability implies continuity, so maybe I could check if it was continuous as a starter?










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$endgroup$

















    2












    $begingroup$


    Consider the following function $f : Bbb R to Bbb R$:



    $$f(x) = begin{cases} sin x & x ge 0 \ x^2 + e^x & x < 0 end{cases}$$



    I was wondering if the above piece-wise function was differentiable over the set of Real numbers R, and how to figure it out.



    I know that differentiability implies continuity, so maybe I could check if it was continuous as a starter?










    share|cite|improve this question











    $endgroup$















      2












      2








      2





      $begingroup$


      Consider the following function $f : Bbb R to Bbb R$:



      $$f(x) = begin{cases} sin x & x ge 0 \ x^2 + e^x & x < 0 end{cases}$$



      I was wondering if the above piece-wise function was differentiable over the set of Real numbers R, and how to figure it out.



      I know that differentiability implies continuity, so maybe I could check if it was continuous as a starter?










      share|cite|improve this question











      $endgroup$




      Consider the following function $f : Bbb R to Bbb R$:



      $$f(x) = begin{cases} sin x & x ge 0 \ x^2 + e^x & x < 0 end{cases}$$



      I was wondering if the above piece-wise function was differentiable over the set of Real numbers R, and how to figure it out.



      I know that differentiability implies continuity, so maybe I could check if it was continuous as a starter?







      calculus






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      share|cite|improve this question













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      edited Jan 13 at 22:09









      zipirovich

      11.3k11731




      11.3k11731










      asked Jan 13 at 21:26









      Oliver BeckOliver Beck

      224




      224






















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          $begingroup$

          That is a good idea. Now check the $x=0$ point. For the right side of the graph, $sin 0 =0$. For the left side, $0^2+e^0=1$. It is not continuous at $x=0$, and is therefore not differentiable at $x=0$.






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            1 Answer
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            active

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            3












            $begingroup$

            That is a good idea. Now check the $x=0$ point. For the right side of the graph, $sin 0 =0$. For the left side, $0^2+e^0=1$. It is not continuous at $x=0$, and is therefore not differentiable at $x=0$.






            share|cite|improve this answer









            $endgroup$


















              3












              $begingroup$

              That is a good idea. Now check the $x=0$ point. For the right side of the graph, $sin 0 =0$. For the left side, $0^2+e^0=1$. It is not continuous at $x=0$, and is therefore not differentiable at $x=0$.






              share|cite|improve this answer









              $endgroup$
















                3












                3








                3





                $begingroup$

                That is a good idea. Now check the $x=0$ point. For the right side of the graph, $sin 0 =0$. For the left side, $0^2+e^0=1$. It is not continuous at $x=0$, and is therefore not differentiable at $x=0$.






                share|cite|improve this answer









                $endgroup$



                That is a good idea. Now check the $x=0$ point. For the right side of the graph, $sin 0 =0$. For the left side, $0^2+e^0=1$. It is not continuous at $x=0$, and is therefore not differentiable at $x=0$.







                share|cite|improve this answer












                share|cite|improve this answer



                share|cite|improve this answer










                answered Jan 13 at 21:37









                Michael WangMichael Wang

                186115




                186115






























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