I see you've uploaded an image with a mathematical exercise in French. Let me break it down for you:

It appears to be a problem involving sequences. The sequence $(u_n)$ is defined recursively with the relation:

$u_{n+1} = 3u_n + 2 \quad \text{with} \quad u_0 = 2 \quad \text{and} \quad u_1 = 4$

You're asked to:

1. Calculate $u_1$ and $u_2$.
2. Prove that the sequence $(u_n)$ is a geometric sequence.
3. Express $u_n$ as a function of $n$.
4. Study the variations of the sequence $(u_n)$.

Would you like me to walk you through solving these steps, or is there a specific part you'd like to focus on?

Here are five related questions:

1. What is a recursive formula and how is it used in this problem?
2. What does it mean for a sequence to be geometric?
3. How do you find a closed-form expression for a recursive sequence?
4. How do you analyze the variations of a sequence?
5. What is the significance of initial conditions in recursive sequences?

Tip: Understanding the recursive definition of the sequence is key to solving problems like this, as it helps in calculating terms and recognizing patterns.