
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 $$f(x)= \frac {(cosx-sinx)\cdot sin2x}{cosx}$$.
(1) Find the domain of $f(x)$ and its smallest positive period;
(2) When $$x∈(- \frac {π}{2}，0]$$, find the maximum and minimum values of the function $f(x)$;
(3) Find the intervals where $f(x)$ is monotonically decreasing.

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