Use the double–angle identity to transform to .
Apply the distributive property.
Multiply .
Multiply by .
Multiply by .
Apply pythagorean identity.
Add and .
Use the double–angle identity to transform to .
Move .
Apply pythagorean identity.
Add and .
Cancel the common factor.
Rewrite the expression.
Convert from to .
Expand (1-cos(2x))/(1+cos(2x))