Giải thích các bước giải:
1) x²-x-6 = x²-3x+2x-6 = x(x-3)+2(x-3) =(x-3)(x+2)
2) x²-8x+12 = x²-6x-2x+12 =x(x-6)-2(x-6) = (x-6)(x-2)
3) x²-12x-13 = x²-13x+x-13 = x(x-13)+(x-13) = (x-13)(x+1)
4) 2x²-5x-3 = 2x²-6x+x-3 =2x(x-3)+(x-3) =(x-3)(2x+1)
5) 3x²+5x-2 = 3x²+6x-x-2 = 3x(x+2)-(x+2) = (x+2)(3x-1)
6) 15x²+9x-10x-6 = 3x(5x+3)-2(5x+3) = (5x+3)(3x-2)