If x = asin θ, y = b tan θ, Prove that .

34

If , Find the value of cos θ.

35

Prove that .

37

If sec θ + tan θ = p. Prove that .

38

If m sin θ + r cos θ = p and m cos θ – n sin θ = q, then prove that m² + n² = p² + q².