Simplify each expression.
√[(1 + cos 76°)/2]

Use the given information to find each of the following.

cot θ/2, given tan θ = -(√5)/2 , with 90° < θ < 180°

Use the given information to find each of the following.

cos θ, given cos 2θ = 1/2 and θ terminates in quadrant II

Use the given information to find each of the following.

sin x, given cos 2x = 2/3 , with π < x < 3π/2

If cos x = -0.750 and sin ≈ 0.6614, then tan x/2 ≈ .

Simplify each expression.

√[(1 + cos 165°)/(1 - cos 165°)]

Simplify each expression. See Example 4.

2 tan 15°/(1 - tan² 15°)

Simplify each expression.

sin 158.2°/(1 + cos 158.2°)

Simplify each expression.

±√[(1 + cos 18x)/2]