Classify into monomials, binomials and trinomials.
`z^2`

Answer

To classify the expression \( z^2 \) into monomials, binomials, and trinomials, we can follow these steps:

### Step 1: Understand the Definitions
- **Monomial**: An algebraic expression that contains only one term.
- **Binomial**: An algebraic expression that contains two terms.
- **Trinomial**: An algebraic expression that contains three terms.

### Step 2: Analyze the Expression
The given expression is \( z^2 \).

### Step 3: Count the Terms
In the expression \( z^2 \):
- There is only one term, which is \( z^2 \).

### Step 4: Classify the Expression
Since \( z^2 \) has only one term, it is classified as a **monomial**.

### Final Answer
The expression \( z^2 \) is a **monomial**.

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