Rationalizing negative fractional exponents.
.pdf Document (91k)
A negative exponent places a factor in the denominator. If the negative exponent is a fraction, that means there is a radical in the denominator that needs to be rationalized to be in simplest form.
In a nutshell, multiply the denominator (and numerator) by the base with a fractional exponent that will produce the exponent of 1.
See examples in the pdf file.