The Total solution for NCERT class 6-12
Find the smallest positive integer value of n for which (1+i) n /(1-i) n-2 is a real number.
Given:
(1+i) n /(1-i) n-2
Z = (1+i) n /(1-i) n-2
Let us multiply anddivide by (1 – i)2
For n = 1,
Z = -2i1+1
= -2i2
= 2, which is a realnumber.
∴ The smallestpositive integer value of n is 1.