因式分解:12x^2-5x-2 5x^2+6xy-8y^2

问题描述:

因式分解:12x^2-5x-2 5x^2+6xy-8y^2

用十字相乘法最简单.
12x²-5x-2
4 1
3 -2
12x²-5x-2=(4x+1)(3x-2)
5x²+6xy-8y²
1 2
5 -4
5x²+6xy-8y²=(x+2)(5x-4)