Question

Using the double angle of half angle formula, how do you simplify `sin8 /(1+cos 8)`?

Answer 1

Use the 2 trig identities:
`sin 2a = 2. sin a. cos a` and
`1 + cos 2a = 2. cos^2 a`

`y = (sin 8x)/(1 + cos 8x)` =`(2. sin 4x. cos 4x)/(2. cos^2 4x)`

`y = tan 4x`