Finding the Domain of Simple Rational Functions 1.7 2006/02/03 09:53:08 US/Central 2006/05/01 18:47:06.583 GMT-5 Pradnya Vinay Bhawalkar pradnyab89@gmail.com Kim Dodge Johnston kim.johnston@fortbend.k12.tx.us Pradnya Vinay Bhawalkar pradnyab89@gmail.com domain fraction function Rational Finding the domain of rational functions with no other complications such as roots/radicals. For fractions, the denominator (the bottom) of the fraction cannot equal 0. Determine domain restrictions by setting the denominator equal to 0 and solving. Find the domain of y1x xx0 Find the domain of y1x5 xx5 since x50, x5 Find the domain of y 4 x 3 x 7 xx7 since x70, x7 Find the domain of y7x52x xx52 since 52x0, x52 Find the domain of y 2 x 3 x 7 x x 3 7 since x 3 and x 7 Find the domain of y 7 x 2 x 2 7 x 3 x x 12 3 since 2 x 2 7 x 3 0 , 2x 1 x 3 0 , 2x 1 0 and x 3 0 , x 12 and x 3 y 2 x 1 x 5 2 -1 x x 5 since x5 2 0 , x5 0 , x 5 Find the domain of y x 3 x 2 25 -1 x x since x 2 25 0 , x2 25 , x Find the domain of y x 7 x 2 2 -1 x x since x 2 2 0 , x2 2 , x Find the domain of y 5 x3 xx3 since x3 0 , x3 0 , x 3 Find the domain of y 4 x 4 x x 4 4 since x 4 0 , x 4 , x -4 and x 4