
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 the function $f(x)=\sin(2x+\phi)+ \sqrt {3}\cos(2x+\phi)$ $(0＜|\phi|＜π)$ which is monotonically decreasing on $[0, \frac {π}{4}]$ and satisfies $f(x)=f( \frac {π}{2}-x)$.
(1) Find the value of $\phi$;
(2) After shifting the graph of $y=f(x)$ to the left by $\frac {π}{3}$ units to obtain the graph of $y=g(x)$, find the analytical expression of $g(x)$.

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