Question

Which choice is equivalent to the expression below? V-64

Answer 1

Answer: E) 8i

Explanation:

By definition, i = sqrt(-1)

Which means,

sqrt(-64) = sqrt(-1*64)

sqrt(-64) = sqrt(-1)*sqrt(64)

sqrt(-64) = i*sqrt(8^2)

sqrt(-64) = i*8

sqrt(-64) = 8i

On the second line, I used the rule sqrt(x*y) = sqrt(x)*sqrt(y). The fourth line used the rule sqrt(x^2) = x when x is nonnegative.