Learn how to solve integrals of rational functions problems step by step online. Solve the trigonometric equation 8cos(2a)=8cos(a)-1. Move everything to the left hand side of the equation. Apply the trigonometric identity: \cos\left(2\theta \right)=2\cos\left(\theta \right)^2-1, where x=a. Multiply the single term 8 by each term of the polynomial \left(2\cos\left(a\right)^2-1\right). We can try to factor the expression 16\cos\left(a\right)^2-7-8\cos\left(a\right) by applying the following substitution.

Solve the trigonometric equation 8cos(2a)=8cos(a)-1