
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 function $f(x)=e^{-x}-ax$ ($x\in \mathbb{R}$).
1. When $a=-1$, find the minimum value of the function $f(x)$.
2. If for $x\geqslant 0$, $f(-x)+\ln (x+1)\geqslant 1$, find the range of the real number $a$.

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