
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
Given the mapping $f: A \rightarrow B$, where set $A = \{-3, -2, -1, 1, 2, 3, 4\}$, and the elements in set $B$ are the images of the elements in $A$ under the mapping $f$, and for any $a \in A$, the corresponding element in $B$ is $|a|$. Determine the set $B$.

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