Find a simple math problem. I'm a little stupid. Do not laugh at me.

① The number under the root sign is ≥0, otherwise it is meaningless.

∴ 1-x2≥0→x2≤ 1 →- 1≤x≤ 1

② The solution |x|≤ 1 is-1≤x≤ 1.

The synthesis is-1≤x≤ 1.

The second formula

Solution 1

① x > 1 or x

② | x | < 2-2 < x < 2

Comprehensive is-2 < x

To sum up, x is empty. . . . .

I haven't touched math for years. What is the answer? Why does it feel wrong?