ln(x^2)<=0
Let's solve in ℝ: ln(x2) ≤ 0
On the logarithm's domain, ln is strictly increasing: ln(x2) ≤ 0 is equivalent to x2 ≤ 1
An even power only depends on the absolute value: x2 ≤ 1 is equivalent to |x| ≤ 1
|A| ≤ B is equivalent to -B ≤ A ≤ B
-1 ≤ x ≤ 1
Candidates, pending the domain check: x ∈ [-1, 1]
Let's find the domain of ln(x2) ≤ 0
For the expression ln(x2) to be defined, we must have: x2 > 0
Any even power is always non-negative in ℝ and equals 0 only when the base itself is 0
Domain constraints: x ≠ 0
▶Solution:   x ∈ [-1, 0) ∪ (0, 1]