Equate coefficients, 1 = 0 = + = −1 1 1 1 = + = − ( + 1) + 1 + 1 1 /3 1 1 1 ∫ = ∫ [ − ] 2 0 ( + 1) 2 0 + 1 Perform the integration, 1 1 1 ∫ [ − ] 2 + 1 0 1 /3 = [ln( ) − ln( + 1)] 2 0 1 /3 = [ln ( )] 2 + 1 0 2 2 Since = cos ( ) 4