Cubes can't work, one is to open the second power and the other is to raise the third power.
The reason is the same as dividing by 2 can't cancel multiplying by 3.
Open three times and cancel three times, open four times and cancel four times, open five times and cancel five times, and so on.
It is an irrational number, that is, an infinite cycle decimal. We use the cube root number 2 to represent it.