
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 parametric equations of curve C, $x=3\cos \phi$, $y=3+3\sin \phi$ ($\phi$ is the parameter), establish a polar coordinate system with the origin as the pole and the non-negative semi-axis of the $x$-axis as the polar axis.
(I) Find the polar equation of curve C.
(II) A line $l$ with a slope angle of $135^{\circ}$ passes through point P(1,2) and intersects curve C at points M and N. Find the value of $\frac{1}{|PM|}+\frac{1}{|PN|}$.

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