If i2=-1 and (-i)2=i2=-1, then √-1 is equal to

Question

If i2=-1 and (-i)2=i2=-1, then √-1 is equal to (A) i (B) -i (C) i and -i (D) None of these

Tardigrade Admin · Accepted Answer

(i)2=-1 and (-i)2-i2=-1 Therefore, square roots of -1 are i,-i. However, by the symbol √-1 we would mean (i) only.

Q. If $i^{2} = - 1$ and $(- i)^{2} = i^{2} = - 1$ , then $- 1$ is equal to