
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 that $a\_1 + \frac{1}{3}a\_2 + \frac{1}{5}a\_3 + ... + \frac{1}{2n-1}a\_n = n$,
(1) Find the general term formula for the sequence ${a_n}$;
(2) Find the sum of the first 84 terms of the sequence ${\frac{1}{\sqrt{a_{n+1}} + \sqrt{a_n}}}$.

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