Question

ааалгебраааа))))))))

Answer 1

$sqrt{(k-1)^2} =|k-1| \ |k-1|=1-k, k-1<0 \ |k-1|=1-k, k<1$

$sqrt{(1+k)^2} =|1+k| \ |1+k|=-1-k, 1+k<0 \ |1+k|=-1-k, k<-1$