这个题,不方便运用十字相乘法来求解.
3x²+2x-6=0
x² + 2x/3 - 2=0
x² + 2x/3 + 1/9 - 19/9 = 0
(x+1/3)² = 19/9
x+1/3 = ±√19/3
x = -1/3 ±√19/3