Question

If f(x)=x^2+1, find and simplify:
(a) f(t+1)
The answer: t^2+2t+2
I do not understand how to workout the problem and get this answer. Please help!

Answer 1

All they're saying is to plug in (t + 1) for x and simplify.

f(x) = x² + 1
f(t + 1) = (t + 1)² + 1
= (t + 1)(t + 1) + 1
= t² + t + t + 1 + 1
= t² + 2t + 2