What exactly is a polynomial

The video tutorial explains the concept of monomials, providing examples such as the number 3, negative X to the 7th, and two X squared. It then discusses what cannot be considered monomials, such as expressions with rational exponents, negative exponents, or multiple variables multiplied together. The tutorial concludes with a formal definition of monomials as the product of a number and a variable, emphasizing the restrictions on exponents and variable combinations.

Explain why negative exponents are not allowed in monomials.

Can a monomial have multiple variables? Justify your answer.