College Algebra\nChapter 1/Section 7\n\nThe quotient of two polynomial functions is called a rational expression. \n\nIf f(x) and g(x) are polynomial functions, then \nf(x)/g(x) is a rational expression. A rational expression is a fraction..\n\nIf f(x) = x/(x - 1), then f(x) is a rational expression in one variable. \n\nIf g(x) = (xy)^2/(x - y)^3, then g(x) is a rational expression in two variables. \n\nIs any of this right? \n\nQuestion \n\nIs there such a thing as a rational expression in more than two variables? If so, can you give two examples?\n\nThank you.