Answer
$(-\infty,-1]\cup(0,1] $.
Work Step by Step
Step 1. For $\frac{(x-1)(x+1)}{x}\le0$, identify boundary points as $x=-1,0,1$.
Step 2. Form intervals $(-\infty,-1],[-1,0),(0,1],[1,\infty)$.
Step 3. Choose test values for each interval $x=-2,-0.5,0.5,2$.
Step 4. Test the inequality to get results: $True,\ False,\ True,\ False$
Step 5. We have the solution $(-\infty,-1]\cup(0,1] $.
