What is the second derivative for #y(x)=5e^(pi x)+cos (y(x))# ?

1 Answer
Sep 26, 2015

#y''=(5pi^2e^(pix) ((1+siny)^2-5e^(pix)cosy))/(1+siny)^3#

Explanation:

#d/dx(y(x))=d/dx(5e^(pix)+cos(y(x))#

#y'=5pie^(pix)-siny*y'#

#y'=(5pie^(pix))/(1+siny)#

#d/dx(y')=(5pi^2e^(pix)*(1+siny)-5pie^(pix)*cosy*y')/(1+siny)^2#

#y''=(5pi^2e^(pix)*(1+siny)-5pie^(pix)*cosy (5pie^(pix))/(1+siny))/(1+siny)^2#

#y''=(5pi^2e^(pix)*(1+siny)-5pie^(pix)*cosy (5pie^(pix))/(1+siny))/(1+siny)^2#

#y''=(5pi^2e^(pix)*(1+siny)^2-25pi^2e^(2pix)*cosy)/(1+siny)^3#

#y''=(5pi^2e^(pix) ((1+siny)^2-5e^(pix)cosy))/(1+siny)^3#