(b) Given that z = e and n is a positive integer, show that 1 Z = cos 0-isin I + 1 = Nosno Bosne. (ii) z" + Hence, by finding the binomial expansion for for (z+1). pcos 30+q cos 0, where p and q are constants to be determined. [(a) z=2+2i or z=-14-2i; (b) p=- , express cos in the form [6] 3 and 4 ] 4