You can
put this solution on YOUR website!i is defined as the

So
i^1 = i
i^2 = -1
i^3 = -i
i^4 = (-1)(-1) = 1
And it repeats in a cycle of 4
i^5 = i^4*i = 1+i = i
i^6 = i^4*i^2 = 1*i^2 = 1 *(-1) = -1
i^7 = i^4*i^3 = 1*i^3 = -i
etc etc
how do you use in a radical? If the value under the radical is negative, then look at that as (-1)*aPositive
for instance

= plus or minus 3i