
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
Evaluate the sum $\sqrt[3]{7 + 2\sqrt{21}} + \sqrt[3]{7 - 2\sqrt{21}}$.
A) $\sqrt[3]{9}$
B) $\sqrt[3]{6}$
C) $\sqrt[3]{7}$
D) $\sqrt[3]{8}$
E) none of these

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