
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 the terminal side of angle $α$ passes through point $P(\frac{4}{5},-\frac{3}{5})$,

(1) Find the value of $\sin α$;

(2) Find the value of $\frac{\sin (\frac{π}{2}-α)}{\sin (α+π)}-\frac{\tan (α-π)}{\cos (3π-α)}$.

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