# How to integrate a constant expression: ∫3 dx?

Integration is one of the most important concepts in calculus. It is the reverse of differentiation. It has many applications in various fields.

## Answer: The integral of the given constant expression ∫3 dx is equal to 3x + C, where C is an arbitrary constant.

Let's understand the solution in detail.

**Explanation:**

Given expression: ∫3 dx

Now, we know that the indefinite integral of any constant a is ax + C, where C is an arbitrary constant.

Hence, similarly, ∫3 dx = 3x + C.