Hello,
first I assume that you used the shift key where you better shouldn't use it. That means your problem reads:
and
means you have to calculate: . Therefore you have to plug the term of the function g in the place of the x in function f:
. That's the result CaptainBlack has already told you.
Same procedure:
. That's the result CaptainBlack has already told you.
To be honest: I can't guess what you have done.
EB