Rationalizing The Denominator 21 = 21∗22 = 22 Why it is important If you don’t, it messes up the limits. Example: x−2x−4 when x = 4, it will be 00 This doesn’t really tell us anything. There is a hole at x=4 x−4(x−4)(x+2) = 1x+2 Law of rationalization aa = a