The correct option is B 1−d,2−a,3−b,4−c
(1) i=eiπ/2i=e−π/2=option (d)
(2) log i=loge |1|eiπ/2
=0+iπ/2=option (a)
(3) log(logi)=log(iπ/2)as log i=iπ/2
=log(π2ei {pi/2)
=logπ2+logeeiπ/2
=logπ2+iπ2 =option (b)
(4) √i+√−1=e(iπ/2)×12+e(−iπ/2)×12
=1√2+i√2+1√2−i√2
√2 =option (c)