Answer :
A rational expression is a fraction in which the numerator and denominator are polynomials and a complex rational expression is a fraction where the numerator and denominator are rational expressions.
For example, we can take the following rational expressions:
[tex]\begin{gathered} f(x)=\frac{x^2-9x+5}{x+1} \\ g(x)=\frac{x^3+2x}{2x^2+8} \end{gathered}[/tex]Both f(x) and g(x) are polynomial functions, we can use f(x) as the numerator of a complex rational expression and g(x) as the denominator to get:
[tex]\frac{\frac{x^2-9x+5}{x+1}}{\frac{x^3+2x}{2x^2+8}}[/tex]Similarly, we can formulate 2 more complex rational expressions like this:
[tex]\begin{gathered} \frac{\frac{x^2^{}+3}{x^3+2x-1}}{\frac{2x-4x^2}{x}} \\ \\ \frac{\frac{3}{x-3}}{\frac{4x+4}{2}} \end{gathered}[/tex]