Fix the Prove One Side Mistake

Understand the problem

1 of 3

First, understand the question

Do not start calculating until the given information and the required answer are clear.

Problem

Prove 1−sin⁡2θcos⁡θ=cos⁡θ\frac{1-\sin^2\theta}{\cos\theta}=\cos\theta.

What are we trying to do?

Start with the left side and simplify it step by step until it becomes coshetacos heta.

Build the solution one reason at a time

Read why each action is needed. Then use it to change the mathematical model.

1−sin⁡2θcos⁡θ\frac{1-\sin^2\theta}{\cos\theta}
→
??
sin⁡2θ+cos⁡2θ=1\sin^2\theta+\cos^2\theta=1

Transform one side. Reach the other side.

Helpful?