Imaginary part of complex 1-I / (1 + I) 2

Imaginary part of complex 1-I / (1 + I) 2

(1-i)/(1+i)²
=(1-i)/(1+2i-1)
=(1-i)/(2i)
=(1-i)i/(-2)
=(i+1)/(-2)
=(-1/2) +(-1/2)i
Imaginary part: - 1 / 2