CPM Homework Help : PC3 Problem 9-31

Simplify each of the following trigonometric expressions.

$\frac{\cot(x)}{\sin(x)}(\sec(x)-\cos(x))$
Hint (a):
1. Change all terms to sine and cosine.
2. Get a common denominator for the terms in the parentheses.
3. Use the Fundamental Pythagorean Identity.

$(\cos(x) + 1)(\cos(x) − 1) + \sin^2(x)$
Hint (b):
1. Multiply out on the left side.
2. Use the Fundamental Pythagorean Identity.