### Home > CCA2 > Chapter 8 > Lesson 8.1.1 > Problem8-17

8-17.

​​Which of the following equations are polynomial functions? For each one that is not, justify why not.

1. $y=3x^2+2x^2+x$

1. $y=(x-1)^2(x-2)^2$

1. $y=x^2+2^x$

1. $y=3x-1$

1. $y=(x-2)^2-1$

1. $y^2=(x-2)^2-1$

1. $y=\frac{1}{x^2}+\frac{1}{x}+\frac{1}{2}$

1. $y=\frac{1}{2}x+\frac{1}{3}$

1. $y=x$

1. $y=-7$

The equations in parts (c), (f), and (g) are not polynomials. Refer to the Math Notes box for this lesson if you are confused.