We all know that i = √(-1) .

and = 1

= i (where n is any positive integer )

=

= -1

So,

(i) L.H.S =

=

=

Since it is of the form

Hence the value of .

(ii)

so its solution would be -1

(iii)

⇒i

So, it is of the form of so the solution would be i.