Question

已知X3+2X2-5x-6=(x+a)（x+b)(x+c),求abc的值

Answer 1

x^3+2x^2-5x-6

=(x^3+x^2)+(x^2-5x-6)

=x^2(x+1)+(x-6)(x+1)

=(x+1)(x^2+x-6)

=(x+1)(x-2)(x+3)

所以：a=1 b=-2 c=3