
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
<sub>ks5u</sub>  
The graph of the function $f(x) = 3\sin x$ is denoted as $C$. Among the following conclusions, the correct ones are __________ (write down all the correct conclusion numbers).  
① The graph $C$ is symmetric about the line $x = 0$; ② The graph $C$ is symmetric about a point;  
③ The function $f(x)$ is increasing in the interval $(-\frac{\pi}{2}, \frac{\pi}{2})$;  
④ The graph of $y = 3\sin 2x$ can be obtained by shifting the graph $C$ to the right by $\frac{\pi}{4}$ units.

Present the answer in LaTex format: \boxed{Your answer}
user