# RATL 2 | Lesson 1 | Try This! (Rational Expressions)

1. Below are non-examples of rational expressions. Why are these not rational expressions? (Hint: Keep in mind the definition of a polynomial.)
1. $$\dfrac{3-\sqrt{x}}{2+x}$$
2. $$\dfrac{x+2}{4+\dfrac{1}{x}}$$
3. $$\dfrac{x-4}{3-3}$$
4. $$2^x$$
1. Generate a list of attributes that keep an expression from being a rational expression.