Here it is with a little more detail:



Give the coefficient 2 a visible exponent of 1



Multiply each of the three exponents inside the 
parentheses by the exponent 4 just outside the 
parentheses and remove the parentheses:



To make the negative exponent positive, move it
to a denominator down below the other factors:



24 means (2)(2)(2)(2) = 16



Edwin