It is given that,
( 1+i 1−i ) m =1
Rationalize the denominator,
( 1+i 1−i × 1+i 1+i ) m =1 ( ( 1+i ) 2 1 2 − i 2 ) m =1 ( 1+ i 2 +2i 1+1 ) m =1 ( 1−1+2i 2 ) m =1
Simplify further,
( i ) m = ( i ) 4 m=4
Therefore, the least integral value of m is 4.
If [1+i1−i]m=1, then find the least positive integral value of m.