Half Angle Formula

Question 1

Using half angles:

1/2 (1-cos(2θ)) = ?

Answer 1

= sin²θ

Question 2

Using half angles:

cos²θ = ?

Answer 2

= 1/2 (1+cos(2θ))

Question 3

Using half angles:

1/2 (1+cos(2θ)) = ?

Answer 3

= cos²θ

Question 4

Using half angles:

sin²θ = ?

Answer 4

= 1/2 (1-cos(2θ))

Question 5

Using half angles:

tan²θ = ?

Answer 5

Question 6

Using half angles:

Answer 6

= tan²θ