
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
Let $S_n$ be the sum of the first $n$ terms of the sequence ${a_n}$. Given that $a_n > 0$ and $a_n^2 + 2a_n = 4S_n + 3$.

(1) Find the general term formula for ${a_n}$.

(2) Let $b_n = \frac{1}{a_n b_{n+1}}$, find the sum of the first $n$ terms of the sequence ${b_n}$.

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