1−i1+i is equal to
cosπ2+isinπ2
cosπ2-isinπ2
sinπ2+icosπ2
None of these
1−i1+i=(1−i)(1−i)(1+i)(1−i)=1+(i)2−2i1+1=-i
Which can be written as cosπ2-isinπ2