Q11 of 153 Page 13

Find the smallest positive integer value of n for which is a real number.

Let us write the given complex number as


Multiplying and dividing with (1-i)2


⇒


⇒


⇒


⇒


We know that i2=-1


⇒


⇒


⇒


⇒


⇒


We know that i2k is real for k≥0.


∴ The least positive integral of n is 1.


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