Evaluate: ∫dx/((1 + x^2)√1 - x^2), x ∈ [0, 1/2 ]

Question

 Evaluate:

\(\int_0^\frac{1}{2}\) dx/((1 + x²)√1 - x²) (Hint: let x = sinθ)

Answer 1

⇒As sec² θ-tan² θ=1