# Is 4 - 3x plus 5x2 a polynomial?

Yes. If you add, subtract or multiply (but not if you divide) any two polynomials, you will get a polynomial.

### What is an example of an expression that is not a polynomial?

A polynomial expression is one with a degree higher than 0. Hence, all constants will meet your criterion. Note that (x+2) or [sin(2x)+4] is a polynomial of degree 1. The following is a trivial (normally ignored; inconsequential) non-polynomial: (5x2 - 2x2 - 3x2 + 2) ======================================