express i-39 (iota raised to the power minus 39) in the form of a+ib

i-39

= 1/ i 39

= 1/ (i2)19 i

= -1/ i {i2 = -1}

now rationalise it,

-1/i x i / i =-i / -1 = i

or 0 +1.i

HOPE THIS WOULD HELP