
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 $\tan (\pi-\alpha)=-3$,
(1) Find the value of $\tan \alpha$.
(2) Find the value of $\dfrac { \sin (π-\alpha)-\cos (π+\alpha)-\sin (2π-\alpha)+\cos (-α)}{\sin ( \dfrac {π}{2}-\alpha )+\cos ( \dfrac {3π}{2}-\alpha )}$.

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