
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
The graphs of four functions, labelled (1) through (4), are shown. The domain of function (2) is $$\{-6, -5, -4, -3, -2, -1, 0, 1\}.$$ Determine the product of the labels of the functions that are invertible. Assume:
- Function (1): $y = x^3 - 3x$
- Function (2): Discrete points shown
- Function (3): $y = -\tan(x)$
- Function (4): $y = 5/x$

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