Q3 (3 points) a) Let a, b e R, not both zero. Find real numbers c, d such that (a + bi)-1 = c + di. b) Find all cube roots of 1 in C. Give their real and imaginary parts explicitly. c) Plot the subsets S2 = {z C : z2 = 1}, S3 = {zEC : 23 = 1} and S = {z C : 24 = 1}.