A rational expression can be said to be the ratio of two polynomials. A rational expression is expressed as a fraction where the numerator and/or the denomiantor are polynomials.
In rational expressions, the denominator must not tend to zero.
Examples of rational expressions are:
[tex]\begin{gathered} \frac{3x+5}{x-3} \\ \\ \frac{x+9}{x^2+8x-9} \\ \\ \frac{(x-1)^2}{x^2+3-2} \end{gathered}[/tex]Therefore, we can say a rational expression is a fraction which has a polynomial in the denominator and/or numerator.
ANSWER:
A rational expression is a fraction which contains a polynomial in the denominator and/or numerator.