Question

Use square roots to solve the equation x2 = –64 over the complex .numbers. Select any solutions that apply.

an 8i
b -8
c -8i^2
d -8i

Answer 1

`x^2=-64\implies x=√(-64)\implies x=√(-1\cdot 64)\implies x=√(-1)\cdot √(64) \\\\\\ x=√(-1)\cdot 8\implies x=i\cdot 8\implies x=8i`