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问题: 分式方程(写检验)

1.5x/x^2+x-6 + 2x-5/x^2-x-12 =7x-10/x^2-6x+8
2.6y+12/y^2+4y+4 - y^2-4/y^2-4y+4 + y^2/y^2-4 =0
3.x^2-8/x^2-10 = x^2-3x+2/x^2-3x

解答:

3)(x^2-8)/(x^2-10)=(x^2-3x+2)/(x^2-3x)
两边同时加1,得 2/(x^2-10)=2/(x^2-3x)
取倒数 x^2-10=x^2-3x
小曲x^2得 -3x=-10
--->x=10/3
2)(6y+12)/(y+2)^2-(y^2-4)/(y-2)^2+y^2/(y^2-4)
--->6/(y+2)-(y+2)/(y-2)-y^2/[(y-2)(y+2)]=0
去分母 6(y-2)-(y+2)^2-y^2=0
--->(6y-12)-(y^2+4y+4)-y^2=0
--->2y-8=0
--->y=4.
1)5x/[(x+3)(x-2)]+(2x-5)/[(x+3)(x-4)]=(7x-10)/[(x-2)(x-4)]
去分母 5x(x-4)+(2x-5)(x-2)=(7x-10)(x+3)
--->(5x^2-20x)+(2x^2-9x+10)=7x^2+11x-30
--->-40x=-40
--->x=1.
检验!还是自己做吧!