2x*5x^3 3x^3*(-1/3x) 3x*(-2x^2) a*(x-y) x^2*(1-x-x^2) (a^2+2ab+3a^2b)

问题描述:

2x*5x^3 3x^3*(-1/3x) 3x*(-2x^2) a*(x-y) x^2*(1-x-x^2) (a^2+2ab+3a^2b)

2x*5x^3 =10x^4
3x^3*(-1/3x) =-x^4
3x*(-2x^2) =-6x^3
a*(x-y) =ax-ay
x^2*(1-x-x^2) =x^2-x^3-x^4
(a^2+2ab+3a^2b)=a^2+2ab+3a^2b