How to Calculate Outputs for Rational Functions In pre-calculus,
you can calculate outputs for rational functions. A rational
function is a function that can be expressed as the quotient of
two polynomials, such that where the degree of q(x) is greater
than zero. Here are the steps involved in finding the outputs of
(and ultimately graphing) rational functions: Search for
vertical asymptotes. Having the variable on the bottom of a
fraction is a problem, because the denominator of a fraction can
never be zero. Usually, some domain value(s) of x makes the
denominator zero. If there exists an x-value that makes the
denominator zero, but not the numerator, then the graph has
what’s called a vertical asymptote at this x-value. Graphing the
vertical asymptote first shows you the number in the domain
where your graph can’t pass through. The graph approaches this
point but never reaches it. With that in mind, what value(s) for
x can you not plug into the rational function? The following
functions are all rational: Tr