(b) By putting z = eie for the unit circle, show that cos 0 = 1/ (z + 1 ) ; ); sin 8-(2-): 2i 1 = = 271 Hence, evaluate the following integral by converting it as a contour integral in the complex plane around the unit circle as contour C. and de de [3-2 cos 0 + sin 0] dz iz (17 marks)