先化简再求值(1-根号a)除以-搜答案-智慧作业帮

（a/(ab-b^2)-b/(a^2-ab))/(（1+a^2+b^2)/2ab)=（a/(b*(a-b))-b/(a*(a-b)))/(（1+a^2+b^2)/2ab)=（(a^2-b^2)/(a*

原式=[X-X/(X-1)]/[1+1/(X²-1)]=[X(X-1)-X]/[X-1+1/(X+1)]分子分母都乘以(X-1)=(X²-2X)(X+1)/[X²-1+1

我分析原题应该是：9根号下1-2sin160°cos340°)除以(cos200°+根号下sin20°^2)根号下sin200°应为：根号下sin20°^2√（1-2sin160°cos340°）/(

[2/(a-1)-1/(a+1)]/[1/(a+1)]=[2/(a-1)-1/(a+1)](a+1)=2(a+1)/(a-1)-1=[2(a+1)-(a-1)]/(a-1)=(a+3)/(a-1)=(

(a+1分之1-a的平方-1分之a-2)除以a+1分之1=1/(a+1)x(a+1)-(a-2)/(a+1)(a-1)x(a+1)=1-(a-2)/(a+1)=(a+1-a+1)/(a+1)=2/(a

原式=a+(1-a)的绝对值∵1-a＜0∴原式=a+(a-1)=2a-1当a=9时原式=2a-1=2×9-1=17

等差1+15=4+12a1+a15=a4+a12所以a1-a4-a8-a12+a15=2则-a8=2a8=-21+15=8+8所以a1+a15=a8+a8=-4S15=(a1+a15)*15/2=-3

原式=(a+2)²/(a+1)÷[(a-1)(a+1)-3]/(a+1)=(a+2)²/(a+1)÷(a²-4)/(a+1)=(a+2)²/(a+1)×(a+1

原式=a+√(a-2)²=a+|a-2|=-1+|-1-2|=-1+3=2即|1-x|-√(x-4)²=2x-5|1-x|-|x-4|=2x-5因为(x-1)-(4-x)=2x-5

原式=(x-4)/(x-1)÷(x²-1-15)/(x-1)=(x-4)/(x-1)÷(x²-16)/(x-1)=(x-4)/(x-1)*(x-1)/(x+4)(x-4)=1/(x

解1/(a+1)-(a+1)/(a²-2a+1)÷(a+1)/(a-1)=1/(a+1)-(a+1)/(a-1)²×(a-1)/(a+1)=1/(a+1)-1/(a-1)=(a-1

原式=(a-2)/(a-4)÷(a²-4a+4)/(a-4)=(a-2)/(a-4)×(a-4)/(a-2)²=1/(a-2)=1/(√3+2-2)=√3/3

原式=(3+a)(3-a)/(a+3)^2x(a+3)/(a-3)a-1/a=-1/a-1/a=-2/a=-2/根号2=-根号2

原式=(a+1)/(a-1)-[a/(1/a)]/(a²-2a+1)=(a+1)/(a-1)-a²/(a-1)²=[(a+1)(a-1)-a²]/(a-1)&s

[1/(a-1)+a/(1-a)]/a=[1/(a-1)-a/(a-1)]/a=[(1-a)/(a-1)]/a=-1/a把a=√2+1代入-1/(√2+1)=-1(√2-1)/(√2+1)(√2-1)

加点括号吧,求你了再问：（a方+2a+1）分之（a方-1）+（a-2）分之（2a-a方）除以（a)其中a=(根号2)+1再答：不知你的“除以（a)”是啥意思？除在哪里？只能给你下式(a^2-1)/(a