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