Thread: Domain of Rational Functions

First of all, what is a rational function?

Secondly, how do I find the domain of rational functions?

Find the domain of each rational function below.

[1] Q(x) = -x(1 - x)/(3x^2 +5x -2)

[2] F(x) = -2(x^2 - 4)/3(x^2 + 4x + 4)

Originally Posted by fdrhs

[SIZE="3"]First of all, what is a rational function?

A rational function is a function of a quotient (fraction) of two polynomial functions.

Secondly, how do I find the domain of rational functions?

The "bad" points are where the denominator is zero.

Find the domain of each rational function below.

[1] Q(x) = -x(1 - x)/(3x^2 +5x -2)

Again the denominator is not zero.
Thus,

Find those .
And then the domain is all EXCEPT the ones you found just above.

Same approach to other problem.