Solve the Absolute Value Equation: |2x + |x - 2|| = 1

Question

2x+x2=1 |2x+|x-2||=1

Video Solution

Step-by-Step Solution

To solve the equation 2x+x2=1 |2x + |x - 2|| = 1 , we need to consider different cases based on the expression within the absolute value signs.

Case 1: x2 x \geq 2

  • Here, x2=x2 |x - 2| = x - 2 .
  • The equation becomes 2x+x2=1 |2x + x - 2| = 1 or 3x2=1 |3x - 2| = 1 .
  • This gives two sub-cases to solve:
    • Sub-case 1.1: 3x2=1 3x - 2 = 1 leads to 3x=3 3x = 3 , so x=1 x = 1 . However, x=1 x = 1 does not satisfy x2 x \geq 2 . Discard this solution.
    • Sub-case 1.2: 3x2=1 3x - 2 = -1 leads to 3x=1 3x = 1 , so x=13 x = \frac{1}{3} . But x=13 x = \frac{1}{3} does not satisfy x2 x \geq 2 . Discard this solution.

Case 2: x<2 x < 2

  • In this case, x2=2x |x - 2| = 2 - x .
  • The equation transforms into 2x+2x=1 |2x + 2 - x| = 1 , then simplifies to x+2=1 |x + 2| = 1 .
  • This leads to two sub-cases:
    • Sub-case 2.1: x+2=1 x + 2 = 1 leads to x=1 x = -1 . Since x=1<2 x = -1 < 2 , it is a valid solution.
    • Sub-case 2.2: x+2=1 x + 2 = -1 leads to x=3 x = -3 . Again, x=3<2 x = -3 < 2 holds, so this is also a valid solution.

Thus, the solutions to the equation are x=1 x = -1 and x=3 x = -3 .

Therefore, the correct answers are x=1 x = -1 and x=3 x = -3 .

Answer

x=1 x=-1 , x=3 x=-3