
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
Let $a < 0$, and the function $f(x) = \frac{1}{2}x^2 + (a-1)x - a\ln x$.
1. If the slope of the tangent to the curve $y = f(x)$ at the point $(2, f(2))$ is -1, find the value of $a$;
2. When $-1 < a < 0$, determine the extreme points of the function $f(x)$.

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