Question 2295
i take it you mean i is "the square root of minus 1"? If so,

if i = {{{sqrt(-1)}}} then square both sides gives {{{i^2}}} = -1.

{{{i^3}}} = {{{i*i^2}}} = -i

{{{i^4}}} = {{{i^2*i^2}}} = -1*-1 = +1

jon