A polynomial is a linear combination of different powers of the same variable, and the degree of a polynomial is given by its highest exponent.
Our polynomial is
![4x-2+x^3+2x^2](https://img.qammunity.org/2023/formulas/mathematics/college/bgggs1lnk45klgskrf0wgni3vprxqfb5dh.png)
The term with the highest exponent is -x³, therefore, the this is a 3rd degree polynomial.