Classify `f: Q->Q` , defined by `f(x)=x^3+1` as injection, surjection or bijection.

Explanation

To classify the function \( f: \mathbb{Q} \to \mathbb{Q} \) defined by \( f(x) = x^3 + 1 \) as an injection, surjection, or bijection, we will follow these steps:

### Step 1: Check if the function is injective (one-one)
A function is injective if different inputs produce different outputs. To check this, we can use the derivative.

1. **Find the derivative of \( f(x) \)**:
\[
f'(x) = 3x^2
...