Question

Prove that
1 + cos 0
1 - cos e
( cosec 0 + cot e )2​

Answer 1

To Prove

→ (cosec∅ - cot∅)² = (1 - cos∅)/(1 + cos∅)

Solution

By replacing values of cosec∅ and cot∅.

L.H.S → (1/sin∅ - cos∅/sin∅)²

→ [(1 - cos∅)/sin∅]²

→ (1 - cos∅)²/sin²∅

Since sin²∅ = 1 - cos²∅

→ (1 - cos∅)²/(1 - cos²∅)

By a² - b² identity we get (1 - cos∅)(1 + cos∅)

→ (1 - cos∅)(1 - cos∅)/(1 - cos∅)(1 + cos∅)

→ (1 - cos∅)/(1 + cos∅) = R.H.S

Q.E.D