The expression 7x3 + 2x2 + 9x + 1 can be classified based on the number of terms it contains:
- Monomial: An expression with only one term. For example, 5x2 is a monomial.
- Binomial: An expression with exactly two terms. An example would be 3x + 4.
- Trinomial: This is an expression that consists of three terms. For instance, x2 + 2x + 1 is a trinomial.
- Polynomial: A polynomial is an expression containing one or more terms, and it can have any number of terms.
Now, in our case, the expression 7x3 + 2x2 + 9x + 1 has four terms:
- 7x3
- 2x2
- 9x
- 1
Since the expression features more than three terms, it does not fit into the categories of monomial, binomial, or trinomial. Therefore, we classify the expression as a polynomial.
In summary, the expression 7x3 + 2x2 + 9x + 1 is a polynomial with four terms.