Question

Express each of the following as single trigonometric ratio

Use double angle formula

a) 2 sin 5x cos 5x
b) cos^2 0 - sin ^2 0
c) 1- 2 sin^2 3x
d) 2 tan 4x / 1-tan^2 4x

Answer 1

a) 2 sin 5x cos 5x=sin10x

b) cos² 0 - sin² 0=cos(2*0)

c) 1- 2 sin² 3x=cos6x

d) 2 tan 4x / (1-tan² 4x)=tan8x