x+2/(x-4)(x-3),-2x/(4-x)(3-x) 通分
问题描述:
x+2/(x-4)(x-3),-2x/(4-x)(3-x) 通分
答
x+2/(x-4)(x-3)=A/(x-4)+B/(x-3)A+B=2-3A-4B=2(1)*3+(2)B=-8A=10则x+2/(x-4)(x-3)=10/(x-4)-8/(x-3)-2x/(4-x)(3-x) =A/(4-x)+B/(3-x) 3A+4B=0A+B=2(1)-(2)*3B=-6A=8则-2x/(4-x)(3-x) =8/(4-x)-6/(3-x)0 0····那个是逗号、、不是一个相减的式子·········x+2/(x-4)(x-3)和 -2x/(4-x)(3-x) 通分……orzx+2/(x-4)(x-3)-2x/(4-x)(3-x) =x+2/(x-4)(x-3)-2x/(x-4)(x-3)=(x+2-2x)/(x-4)(x-3)==(2-x)/(x-4)(x-3)