Identify monomials, binomials and trinomials from the following algebraic expressions :
`xy+yz+zx`

Answer

To identify whether the given algebraic expression \( xy + yz + zx \) is a monomial, binomial, or trinomial, we will follow these steps:

### Step 1: Understand the definitions
- **Monomial**: An expression that contains only one term. For example, \( 3x \) or \( 5y^2 \).
- **Binomial**: An expression that contains two distinct terms. For example, \( x + y \) or \( a^2 + b^2 \).
- **Trinomial**: An expression that contains three distinct terms. For example, \( x + y + z \) or \( a^2 + b^2 + c^2 \).

### Step 2: Analyze the given expression
The expression provided is \( xy + yz + zx \).

### Step 3: Count the terms
- The expression has three parts: \( xy \), \( yz \), and \( zx \).

### Step 4: Check if the terms are distinct
- Each term \( xy \), \( yz \), and \( zx \) is different from the others. They are not like terms.

### Step 5: Classify the expression
Since there are three distinct terms in the expression \( xy + yz + zx \), we classify it as a **trinomial**.

### Final Answer
The expression \( xy + yz + zx \) is a **trinomial**.

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