问一道六升初一的数学题36mn²(y-x)+27n³(x-y)+12m²打错了,应该是36mn²(y-x)+27n³(x-y)+12m² n(x-y)
问题描述:
问一道六升初一的数学题
36mn²(y-x)+27n³(x-y)+12m²
打错了,应该是36mn²(y-x)+27n³(x-y)+12m² n(x-y)
答
36mn²(y-x)+27n³(x-y)+12m² n(x-y)
=n²[27n(x-y)-36m(x-y)]+12m² n(x-y)
=n[27n²(x-y)-36mn(x-y)+12m²(x-y)]
=3n(x-y)(9n²-12mn+4m²)
=3n(x-y)(3n-2mm)²
答
36mn²(y-x)+27n³(x-y)+12m² n(x-y)
=(y-x)(36mn^2-27n^3-12m^2n)
=3n(y-x)(12mn-9n^2-4m^2)
=3n(x-y)(2m-3n)^2
答
是因式分解吧.
3n(4m²-12mn+9n²)(x-y)
=3n(x-y)(2m-3n)²
答
题目的要求是什么 3n(x-y)(2m-3n)*2