
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 $f(x)=\frac{(x+a)\ln x}{x+1}$, the tangent line to the curve $y=f(x)$ at the point $(1,f(1))$ is perpendicular to the line $2x+y+1=0$.
(I) Find the value of $a$;
(II) If $\forall x\in[1,+\infty)$, $f(x)\leqslant m(x-1)$ always holds, find the range of the real number $m$.

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