已知：(4x+1)/(x-2)(x-5)=A/(x-5)+B/(x-2)，则A= ，B=

显示全部楼层 · 2011-2-26 17:18:23

(4x+1)/(x-2)(x-5)=A/(x-2)+B/(x-5) (4x+1)/(x-2)(x-5)=[A(x-5)+B(x-2)]/(x-2)(x-5) 4x+1=(A+B)x-5A-2B 因为等式总能成立所以 A+B=4, -5A-2B=1 解这个方程组得到 A=-3, B=7...

千问 · 2011-2-26 17:18:23

4x+1/（x-2）（x-5）=A/x-5+B/x-24x+1/（x-2）（x-5）=(A/(x-5) * (x-2)(x-5)+(B/(x-2) * (x-2)(x-5)/(x-2)(x-5)4x+1/(x-2)(x-5)=A(x-2)+B(x-5)/(x-2)(x-5)4x+1=A(x-2)+B(x-5)4x+1=Ax-2...

千问 · 2011-2-26 17:18:23

已知：(4x+1)/[(x-2)(x-5)]=A/(x-5)+B/(x-2)，?A/(x-5)+B/(x-2)=[A(x-2)+B(X-5)]/[(x-2)(x-5)]=[(A+B)x+(-2A-5B)]/[(x-5)(x-2)]A+B=4-2A-5B=1解二元一次方程组得:A=7,B=-3....