有几道分式的计算题不会做计算题有两个:(1/m²-m)+(m-5/2m²-2)((a/a-b)+(b/b-a))÷1/a+b还有四个解方程的:(1/x+2)+(1/x-2)=4/x²-4(3x/x+2)+(2/x-2)=3(1-x/x-2)=(1/2-x)-23/2-(1/3x-1)=5/6x-2
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![有几道分式的计算题不会做计算题有两个:(1/m²-m)+(m-5/2m²-2)((a/a-b)+(b/b-a))÷1/a+b还有四个解方程的:(1/x+2)+(1/x-2)=4/x²-4(3x/x+2)+(2/x-2)=3(1-x/x-2)=(1/2-x)-23/2-(1/3x-1)=5/6x-2](/uploads/image/z/4342679-71-9.jpg?t=%E6%9C%89%E5%87%A0%E9%81%93%E5%88%86%E5%BC%8F%E7%9A%84%E8%AE%A1%E7%AE%97%E9%A2%98%E4%B8%8D%E4%BC%9A%E5%81%9A%E8%AE%A1%E7%AE%97%E9%A2%98%E6%9C%89%E4%B8%A4%E4%B8%AA%EF%BC%9A%281%2Fm%26%23178%3B-m%29%2B%28m-5%2F2m%26%23178%3B-2%29%EF%BC%88%28a%2Fa-b%29%2B%EF%BC%88b%2Fb-a%EF%BC%89%EF%BC%89%C3%B71%2Fa%2Bb%E8%BF%98%E6%9C%89%E5%9B%9B%E4%B8%AA%E8%A7%A3%E6%96%B9%E7%A8%8B%E7%9A%84%EF%BC%9A%EF%BC%881%2Fx%2B2%EF%BC%89%2B%EF%BC%881%2Fx-2%EF%BC%89%3D4%2Fx%26%23178%3B-4%EF%BC%883x%2Fx%2B2%EF%BC%89%2B%EF%BC%882%2Fx-2%EF%BC%89%3D3%EF%BC%881-x%2Fx-2%EF%BC%89%3D%281%2F2-x%29-23%2F2-%281%2F3x-1%29%3D5%2F6x-2)
有几道分式的计算题不会做计算题有两个:(1/m²-m)+(m-5/2m²-2)((a/a-b)+(b/b-a))÷1/a+b还有四个解方程的:(1/x+2)+(1/x-2)=4/x²-4(3x/x+2)+(2/x-2)=3(1-x/x-2)=(1/2-x)-23/2-(1/3x-1)=5/6x-2
有几道分式的计算题不会做
计算题有两个:
(1/m²-m)+(m-5/2m²-2)
((a/a-b)+(b/b-a))÷1/a+b
还有四个解方程的:
(1/x+2)+(1/x-2)=4/x²-4
(3x/x+2)+(2/x-2)=3
(1-x/x-2)=(1/2-x)-2
3/2-(1/3x-1)=5/6x-2
有几道分式的计算题不会做计算题有两个:(1/m²-m)+(m-5/2m²-2)((a/a-b)+(b/b-a))÷1/a+b还有四个解方程的:(1/x+2)+(1/x-2)=4/x²-4(3x/x+2)+(2/x-2)=3(1-x/x-2)=(1/2-x)-23/2-(1/3x-1)=5/6x-2
计算题:
[1/(m²-m)]+[(m-5)/(2m²-2)]
={ 1/[m(m-1)] }+{ (m-5)/[2(m+1)(m-1)] } 通分,最简公分母是2m(m+1)(m-1)
={ 2(m+1)/[2m(m+1)(m-1)] }+{ m(m-5)/[2m(m+1)(m-1)] }
=[2(m+1)+m(m-5)]/[2m(m+1)(m-1)]
=(2m+2+m²-5m)/[2m(m+1)(m-1)]
=(m²-3m+2)/[2m(m+1)(m-1)]
=(m-1)(m-2)/[2m(m+1)(m-1)]
=(m-2)/[2m(m+1)]
[a/(a-b)+b/(b-a)]÷[1/(a+b)]
=[a/(a-b)-b/(a-b)]×(a+b)
=[(a-b)/(a-b)]×(a+b)
=1×(a+b)
=a+b
解方程:
[1/(x+2)]+[1/(x-2)]=4/(x²-4) 方程两边同时乘最简公分母(x²-4)
x-2+x+2=4
2x=4
x=2
检验:把x=2代入x²-4=2²-4=4-4=0
经检验x=2是原方程的增根,原方程无解
[3x/(x+2)]+[2/(x-2)]=3 方程两边同时乘最简公分母(x+2)(x-2)
3x(x-2)+2(x+2)=3(x+2)(x-2)
3x²-6x+2x+4=3x²-12
-6x+2x=-12-4
-4x=-16
x=4
检验:把x=4代入(x+2)(x-2)=(4+2)(4-2)=12≠0
经检验x=4是原方程的根
(1-x)/(x-2)=[1/(2-x)]-2 方程两边同时乘最简公分母(x-2)
1-x=-1-2(x-2)
1-x=-1-2x+4
-x+2x=-1+4-1
x=2
检验:把x=2代入x-2=2-2=0
经检验x=2是原方程的增根,原方程无解
3/2-[1/(3x-1)]=5/(6x-2) 方程两边同时乘最简公分母2(3x-1)
3(3x-1)-2=5
9x-3-2=5
9x=5+3+2
9x=10
x=10/9
检验:把x=10/9代入2(3x-1)=2(3×10/9-1)=2×(10/3-1)=14/3≠0
经检验x=10/9是原方程的根