
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 in the rectangular coordinate plane, the absolute difference of the distances from a point to two fixed points $A(-2,0)$ and $B(2,0)$ is equal to $2$, the trajectory of this point is $E$. If $C$ is a point on the trajectory $E$, and the line $BC$ is perpendicular to the $x$-axis, then find the value of $\overrightarrow{AC} \cdot \overrightarrow{BC}$.

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