Question

What is -i^2?

Answer 1

Always make sure to make use of brackets if they help you (and others) understand the problem, because:
\[\large (-i)^2 \neq -(i)^2 \]
I guess you're dealing with this one \(-(i)^2\), you should know that \(i^2=-1\) and the rest is algebra.

Answer 2

That's great thank you so much, might even start using brackets :).

Answer 3

I would gues that it's (-i)^2
In which case treat it as (-1*i)^2
Which is the same as (-1)^2 * (i)^2

Answer 4

so i think how is wrote there this mean that -i^2 = - (-1) = + 1