Express each of the following in the form (a + ib) and find its multiplicative inverse:
(i) 
(ii) 
(iii) 
(i) Let 
∴ the multiplicative inverse of 
(ii) Let 
z = - 1 + i
⇒ |z|2 = ( - 1)2 + (1)2 = 1 + 1 = 2
∴ the multiplicative inverse of 
(iii) Let 
Z = - 1 + i√3
⇒ |z|2 = ( - 1)2 + (√3)2 = 1 + 3 = 4
∴ the multiplicative inverse of 
1