
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 $f\_1(x) = \sin x + \cos x$, denote ${f_2}(x) = {f'_1}(x)$, ${f_3}(x) = {f'_2}(x)$, ..., ${f_n}(x) = f'_{n - 1}(x)\ (n \geqslant 2)$, find the value of ${f_1}\left( {\frac{{\pi }}{2}} \right) + {f_2}\left( {\frac{{\pi }}{2}} \right) + \ldots + {f_{2018}}\left( {\frac{{\pi }}{2}} \right)$.

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