How do you use the chain rule to differentiate y=(cosx/(1+sinx))^5?

1 Answer
Sep 20, 2017

-5(cos^4x)/(1+sinx)^5

Explanation:

y=(cosx/(1+sinx))^5
dy/dx=d/dx((cosx/(1+sinx))^5)
=5(cosx/(1+sinx))^4*(((1+sinx)*(d/dx(cosx))-cosxd/dx(1+sinx))/(1+sinx)^2)

=5(cosx/(1+sinx))^4*(((1+sinx)*(-sinx)-cosx(cosx))/(1+sinx)^2)

=5(cosx/(1+sinx))^4*((-sinx-sin^2x-cos^2x)/(1+sinx)^2)

=5(cosx/(1+sinx))^4*((-sinx-(sin^2x+cos^2x))/(1+sinx)^2)

=5(cosx/(1+sinx))^4*((-sinx-1)/(1+sinx)^2)

=5(cosx/(1+sinx))^4*(-1)/(1+sinx)
=-5(cos^4x)/(1+sinx)^5