Prove that
Use integration by parts
Let, x = sin t
⇒ dx = cos t dt
At x = 0, t = 0
At x = 1, t = π/2
Use integration by parts
Let, …(1)
Use King theorem of definite integral
…(2)
Adding eq.(1) and eq.(2)
Let, 2t = z
⇒ 2 dt = dz
At t = 0, z = 0
At t = π/2, z = π