Verify:

sin60 = 2sin30 cos30

State whether the following are true or false. Justify your answer:

(1) sin θ = , for some angle having measure θ.

(2) cos θ = , for some angle having measure θ.

(3) cosecA = for some measure of angle A.

(4) The value of tanA is always less than 1.

(5) secB = for some ∠B.

(6) cos θ = 100 for some angle having measure θ.

Verify:

cos60 = 1 – 2sin²30 = 2cos²30 – 1 = cos²30 – sin²30

Verify:

sin60 =

Verify:

cos60 =