7

Set 12: Linear Inequalities (Advanced)

Explanation

Answer: A

Solve: x2<1||x| - 2| < 1

A.

3<x<1-3 < x < -1 or 1<x<31 < x < 3

✓ Correct
B.

1<x<31 < x < 3

C.

3<x<3-3 < x < 3

D.

x<1x < -1 or x>1x > 1

Detailed Explanation

Choice A is correct. Choice A is the correct answer. Nested absolute value. 1. Outer Layer: 1<x2<1-1 < |x| - 2 < 1 2. Add 2: 1<x<31< |x| < 3 3. Split: This means distance from 0 is between 1 and 3. 4. Intervals: (1,3)(1, 3) and (3,1)(-3, -1). 5. Inequality: 1<x<31< x < 3 or 3<x<1-3 < x < -1 Strategic Tip: Visualize this on a number line: two symmetric bands away from zero. Choice B is incorrect because it misses the negative band. Choice C is incorrect because it includes the gap [1,1][-1, 1]. Choice D is incorrect because it includes large numbers.

Key Steps:

The correct answer is 3<x<1-3 < x < -1 or 1<x<31< x < 3

Why others are wrong:
B: Choice B is incorrect and may result from a calculation error.
C: Choice C is incorrect and may result from a calculation error.
D: Choice D is incorrect and may result from a calculation error.

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