Question

if angle A = 30° and show that sin A = to root 1 minus Cos 2A upon 2​

Answer 1

Given: ∠A = 30°

To Prove: sinA = √[(1 - Cos2A)/2]

Proof: In attachment

Here, we have some concepts through which you can understand question and solution better.

Concepts

• sin30° = ½
• cos60° = sin30° = ½

Remember

1. Don't forget cos2A where 2 is in Multiplication with angle A.
2. Solve factional values careful.