Question

x的平方加2x减2等于0

Answer 1

x ² + 2 x - 2 = 0

x ² + 2 x + 1 = 2 + 1

（x + 1）² = 3

x + 1 = ± √3

x = ± √3 - 1

x1 = √3 - 1

x2 = - √3 - 1