为什么3x^2+11xy+10y^2=(3x+5y)(x+2y)

问题描述:

为什么3x^2+11xy+10y^2=(3x+5y)(x+2y)

3x^2+11xy+10y^2=(3x+5y)(x+2y)
^^

3x^2+11xy+10y^2
=3x^2+6xy+5xy +10y^2 11xy 折成两项
=3x(x+2y)+5y(x+2y) 分组分解
=(3x+5y)(x+2y)