2
algebra

Solve: 2x132||2x - 1| - 3| \leq 2

A

2x0-2 \leq x \leq 0 or 1x31 \leq x \leq 3

B

2x3-2 \leq x \leq 3

C

1x31 \leq x \leq 3

D

x0x \leq 0 or x1x \geq 1

Correct Answer: A

Choice A is the correct answer. Unwrap the nested absolute value.

  1. Outer: 22x132-2 \leq |2x - 1| - 3 \leq 2
  2. Add 3: 12x151 \leq |2x - 1| \leq 5
  3. Split: Distance is between 1 and 5.
    • Case A: 12x151 \leq 2x - 1 \leq 5
      • Add 1: 22x61x32 \leq 2x \leq 6 \rightarrow 1 \leq x \leq 3
    • Case B: 52x11-5 \leq 2x - 1 \leq -1
      • Add 1: 42x02x0-4 \leq 2x \leq 0 \rightarrow -2 \leq x \leq 0
  4. Combine: [2,0][1,3][-2, 0] \cup [1, 3]

?�� Strategic Tip:u[a,b]|u| \in [a, b] means u[a,b]u \in [a, b] or u[b,a]u \in [-b, -a].

Choice B is incorrect because it includes the gap (0,1)(0, 1). Choice C is incorrect because it misses the negative interval. Choice D is incorrect because it includes large numbers.