3x+5/(x+2)(x+3)=A/(x+2)+B/(X+3),求AB的值

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3x+5/(x+2)(x+3)=A/(x+2)+B/(X+3),求AB的值

3x+5/(x+2)(x+3)=A/(x+2)+B/(X+3),求AB的值
3x+5/(x+2)(x+3)=A/(x+2)+B/(X+3),求AB的值

3x+5/(x+2)(x+3)=A/(x+2)+B/(X+3),求AB的值
原题你少些了一个括号吧?否则结构不对称就不象数学题.
A/(x+2)+B/(x+3)
=[A(x+3)+B(x+2)]/(x+2)(x+3)
=[(A+B)x+(3A+2B)]/(x+2)(x+3)
=(3x+5)/(x+2)(x+3)
所以
A+B=3
3A+2B=5
然后呢 ,A=-1,B=4
难道不对?为啥不给最佳~