How do you convert from a radical expression to a rational exponent?

im just a little confused so if someone could explain this to me, thatd be great!

 The denominator of the raised fraction is what goes on the outside of the square root. So if you had 2 raised to 1/3, you'd put the 3 raised outside to the left of the radical and the 2 inside. They give the same answer, so if you know one, you can always play with the other until you get the same answer. My teacher told us in Calculus a funny/weird way to remember it is the "bottom (of the raised fraction) goes in the crack (of the radical)." Does this help??