先化简,再求值(a 1分之2-搜答案-神马作文网

x/(x-3)-3x/(x^2-3x)-3/x通分得=x^2/(x^2-3x)-3x/(x^2-3x)-3*(x-3)/(x^2-3x)=(x^2-3x-3x+9)/(x^2-3x)=(x-3)(x-

=[(a²-4)/(a-2)]×1/a(a+2)=[(a+2)(a-2)/(a-2)]×1/a(a+2)=(a+2)×1/a(a+2)=1/a

m/(m-n)-n/(m+n)+2mn/(m²-n²)=[m(m+n)-n(m-n)+2mn]/(m²-n²)=(m²+n²)/(m

m²-m分之m²-2m+1=(m-1)²/m(m-1)=(m-1)/m=(92-1)/92=91/92

4/(a^2-4)+2/(a+2)-1/(a-2)=4/(a+2)(a-2)+2(a-2)/(a+2)(a-2)-(a+2)/(a+2)(a-2)=[4+2a-4-a-2]/(a+2)(a-2)=(a

=(a-3)/2(a-2)÷[5/(a-2)-(a+2)(a-2)/(a-2)]=(a-3)/2(a-2)÷(5-a²+4)/(a-2)=(a-3)/2(a-2)×[-(a-2)/(a+3)

（1+1/(x-1))÷x/(x²-1)=x/(x-1)÷x/(x+1)(x-1)=x/(x-1)×(x+1)(x-1)/x=x+1代入可得结果等于-1

2分之3m-（2分之5m-1）+3(4-m)=2分之3m-2分之5m+1+12-3m=-4m+13=-4*3+13=1

您好：x-2＞0x>22x+1＜82x

原式=(x-1)(x+1)/(x+2)*(x+2)/x-1=x+1然后代入数值即可很高兴为您解答,【学习宝典】团队为您答题.请点击下面的【选为满意回答】按钮,

（a+2a+1）/（a-1）-a/(a-1)=(a+1)^2/(a+1)(a-1)-a/(a-1)=(a+1)/(a-1)-a/(a-1)=1/(a-1)由a=根号3+1,所以原式=1/(a-1)=1

再求值m平方+m-2分之1+m除于m-2+m+2分之3

原式＝[2x(x+2)-x(x-2)]/(x²-4)＋x/(x²-4)＝(x²+7x)/(x²-4)＝[x(x+7)]/[(x+2)(x-2)]代入x＝5原式＝

原式=（2aa−1-aa−1）÷a=aa−1×1a=1a−1，当a=2+1时，原式=12+1−1=12=22．

原式=2x-1-16+8x-16=10x-33将x=4/5代入上式得上式=4/5*10-33=-25

=（x+1）/（（2*x+1+x^2）/x）=（x+1）/（（x+1）^2/x）=（x+1）*x/（x+1）^2=x/（x+1）代入x=-3/2得到：原式=3

(a-2)分之a-(a²-2a)分之2a-a分之2=[a(a-2)]分之a²-[a(a-2)]分之(2a)-[a(a-2)]分之[2(a-2)]=[a(a-2)]分之[a²