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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