
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 the derivative of the function $f(x)$ be $f^{(1)}(x)$, the derivative of $f^{(1)}(x)$ be $f^{(2)}(x)$, ..., the derivative of $f^{(n-1)}(x)$ be $f^{(n)}(x)\ (n\in\mathbb{N}^{*})$. If $f(x)$ can be differentiated $n$ times, then $f(x)$ can be approximately represented as: $f(x)≈f(0)+ \frac{f^{(1)}(0)}{1!}x+ \frac{f^{(2)}(0)}{2!}x^{2}+ \frac{f^{(3)}(0)}{3!}x^{3}+…+ \frac{f^{(n)}(0)}{n!}x^{n}$. If $n=4$, according to this conclusion, the approximate estimation of $\cos 2$ is \_\_\_\_\_\_ (represented as a fraction).

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