What is the square root of 64 cubed?

Answer 1

64 x 64 x 64 = 262,144

√ 262,144 = 512

Another way of arriving at this is to take the square root of 64, and cube it - 8 x 8 x 8 also = 512

Answer 2

sqrt(-643) = ± 512*i where i is the imaginary square root of -1.