What number to the 4th power makes 256?

We could work this out using log, but an easier way would be to find the square root of the square root.

Because of the way indices work, ((x) ²) ² = x⁴

so;

= √√256

= √16

= 4

4x4x4x4=256 or √256=16 and √16=4 your answer is (+-) 4