Given f(x)=sinx and g(x)=cosx, find f(g(pi/2))=0? Show all your steps.

I dont understand how to find f(g(pi/2))=0 through f(g(x))

1 Answer
Feb 28, 2018

Start from the inside an work toward the outside.

This means that you start with #g(x) = cos(x)#

Substitute #x = pi/2# into #g(x)#

#g(pi/2) = cos(pi/2)#

#g(pi/2) = 0#

We know that #g(pi/2) = 0#, therefore, we can substitute 0 into #f(x) = sin(x)#:

#f(0) = sin(0)#

#f(0) = 0#