The HCF of two expressions a and b is 1. Their LCM is

Options

A. (a+b)
B. (a-b)
C. ab
D. 1/ab

Answer

To find the LCM of two expressions \( a \) and \( b \) given that their HCF is 1, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the relationship between HCF and LCM**:
The relationship between the HCF (Highest Common Factor) and LCM (Lowest Common Multiple) of two numbers can be expressed with the formula:
\[ \text{HCF} \times \text{LCM} = a \times b \]

2. **Identify the given values**:
We are given that the HCF of \( a \) and \( b \) is 1. Therefore, we can substitute this value into the formula:
\[ 1 \times \text{LCM} = a \times b \]

3. **Simplify the equation**:
Since multiplying by 1 does not change the value, we can simplify the equation to:
\[ \text{LCM} = a \times b \]

4. **Conclusion**:
Therefore, the LCM of the expressions \( a \) and \( b \) is:
\[ \text{LCM} = a \times b \]

### Final Answer:
The LCM of the two expressions \( a \) and \( b \) is \( a \times b \).

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