已知3x+4/x2+x-6=A/x-2+B/x+3,求A、B的值
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已知3x+4/x2+x-6=A/x-2+B/x+3,求A、B的值
已知3x+4/x2+x-6=A/x-2+B/x+3,求A、B的值
已知3x+4/x2+x-6=A/x-2+B/x+3,求A、B的值
(3x+4)/(x^2+x-6)=A/(x-2)+B/(x+3)
(3x+4)/(x^2+x-6)=A(x+3)/(x-2)(x+3)+B(x-2)/(x-2)(x+3)
(3x+4)/(x^2+x-6)=[A(x+3)+B(x-2)]/(x-2)(x+3)
(3x+4)/(x^2+x-6)=(Ax+3A+Bx-2B)/(x^2+x-6)
(3x+4)/(x^2+x-6)=(Ax+Bx+3A-2B)/(x^2+x-6)
(3x+4)/(x^2+x-6)=[(A+B)x+3A-2B]/(x^2+x-6)
A+B=3
3A-2B=4
解得
A=2
B=1
(3x+4)/(x^2+x-6)=A/(x-2)+B/(x+3)
(3x+4)/(x^2+x-6)=A(x+3)/(x-2)(x+3)+B(x-2)/(x-2)(x+3)
(3x+4)/(x^2+x-6)=[A(x+3)+B(x-2)]/(x-2)(x+3)
(3x+4)/(x^2+x-6)=(Ax+3A+Bx-2B)/(x^2+...
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(3x+4)/(x^2+x-6)=A/(x-2)+B/(x+3)
(3x+4)/(x^2+x-6)=A(x+3)/(x-2)(x+3)+B(x-2)/(x-2)(x+3)
(3x+4)/(x^2+x-6)=[A(x+3)+B(x-2)]/(x-2)(x+3)
(3x+4)/(x^2+x-6)=(Ax+3A+Bx-2B)/(x^2+x-6)
(3x+4)/(x^2+x-6)=[(A+B)x+3A-2B]/(x^2+x-6)
A+B=3
3A-2B=4
解得A=2 B=1
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