
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
In the Cartesian coordinate system, O is the origin, and the equation of the parabola E is $y^2 = 4x$. Let M(1, -3) and N(5, 1) be two points such that the line MN intersects the parabola at points A and B. Find the measure of $\angle AOB$.

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