CPM Homework Help : PC3 Problem 1-46

Let $f(x)=2x^2-3$ . Evaluate:

$f(3b)$
Hint (a):
Use ( ) when substituting to avoid errors.
Step (a):
$f(3b)=2(3b)^2-3$

$f(a+1)$
Hint (d):
Do not forget the middle term when rewriting $(a+1)^2$ .
Answer (d):
$2a^2+4a−1$