CPM Homework Help : PCT Problem 4-8

Given the equation $s^2 + c^2 = 1$ , simplify each of the following expressions.

Hint:

Rewrite the given equation in its various forms.
Substitute the appropriate expressions in the problems below.

Forms:

$s^2 = 1 − c^2$
$c^2 = 1 − s^2$

$4 − 4s^2$
Hint (f):
Factor out a $4$ first. Then substitute an expression for $s^2$ .