√[(2x + 1)/(x - 1)], |2x - 1| ≥ x - 1, √2x + 1 ≤ x - 1, | 2x - 1 | - x = 1, |2x - 1| - x = 1, (2x - 1) : (x - 1), |2x - 1| = |x + 1|, |2x-1|=x+1, (2x + 1)² = (x − 1)²