What is the definition of a polynomial expression?

A polynomial expression is defined as an algebraic expression that involves variables raised to whole number powers. This means that polynomials can consist of multiple terms, where each term is a product of a coefficient and a variable raised to a non-negative integer exponent.

For example, in the polynomial ( 3x^2 + 2x + 5 ), (3), (2), and (5) are coefficients, while (x^2) and (x) represent the variables raised to whole number powers (2 and 1, respectively). The key characteristic of a polynomial is that the powers of the variable must be whole numbers, which distinguishes polynomials from other types of algebraic expressions that may include negative exponents, fractional exponents, or irrational numbers.

This definition encapsulates the essence of what makes a polynomial distinct within algebra, emphasizing the condition of whole number exponents for its terms.