
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 $\frac{\sin x + \cos x}{\sin x - \cos x} = 3$.

(1) Find the value of $\tan x$;

(2) If $x$ is an angle in the third quadrant, simplify the trigonometric expression $\sqrt{\frac{1 + \sin x}{1 - \sin x}} - \sqrt{\frac{1 - \sin x}{1 + \sin x}}$ and evaluate its value.

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