先化简在求值其中a满足a²-a-1=0

a/a+1-a平方-3a/a+3除以a平方-6a+9/a平方-9,其中a=-2=a/(a+1)-a(a+3)/(a+3)÷(a-3)²/(a-3)(a+3)=a/(a+1)-a÷(a-3)/

3(a+1)^2-(a+1)(2a-1)=3a^2+6a+3-2a^2-a+1=a^2+5a+4=3-5√3+4=7-5√3

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

（a-4)a-(a+6)=a²-4a-a-6=a²-5a-6=(a-6)(a+1)把a=-1/2代人上式得：（-1/2-6)(-1/2+1)=-13/2×1/2=-13/4

(a二次方-4/a二次方-4a+4-1/2-a）÷2/a二次方-2a=[（a-2）（a+2）/(a-2)²-1/(2-a)]×a（a-2）/2=[(a+2)/(a-2)+1/(a-2)]×a

你的题目估计抄错了!应该是：2a﹙a＋b﹚－﹙a＋b﹚²＝﹙a＋b﹚﹙2a－a－b﹚＝﹙a＋b﹚﹙a－b﹚＝a²－b²＝﹙√2011﹚²－﹙√2010﹚

1原式=6a^3-12a^2-2aa=-1时,原式=-162原式=-60xy,所以原式=60*2008^2=2419238403原式=9再问：第三题可以有过程吗，谢谢了再答：3原式=4x^2+4x+1

原式=(a-1)/(a+2)×(a+2)(a-2)/(a-1)²×(a+1)(a-1)=(a-2)(a+1)=a²-a-2∵a²-a=0∴原式=0-2=-2

(a-1)/(a+2)*(a^2-4)/(a^2-2a+1)÷1/(a^2-1)=(a-1)/(a+2)*(a+2)(a-2)/(a-1)^2*(a+1)(a-1)=(a+1)(a-2)=a^2-a-

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

(a+b)(a-b)+a(2b-a)=a²-b²+2ab-a²=2ab-b²∴当a=1.5,b=2时,原式=2×1.5×2-2²=6-4=2

a²-a-3=0所以a²=a+3原式=a²(a-3)/(a-2)÷[5-(a+2)(a-2)]/(a-2)=a²(a-3)/(a-2)×[-(a-2)/(a+3

即a+3b+1=02a-4=0所以a=2b=-(a+1)/3=-1所以原式=3a²b-(2ab²-2ab+3a²b)+2ab=3a²b-2ab²+2a

先化简,后求值:a-1/2(4a-b)+3(a-1/2b),其中a、b满足(a-1/2)²+|b+1|=0.a=1/2,b=-1代入得1/2-1/2(2+1)+3(1/2+1/2)=2关于x

(2a-a^2)(a^2+4a+3)=a(2-a)(a+3)(a+1)(a^2+a)(a^2-5a+6)=a(a+1)(a-2)(a-3)所以[(2a-a^2)(a^2+4a+3)]/[(a^2+a)

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

原式=(a²-6a+8)-(a²-4a+3)=a²-6a+8-a²+4a-3=-2a+5=-2×(-5/2)+5=5+5=10

a²-1/a-1×根号（a²-2a+1）/a²-a,=(a+1)*|a-1|/[a(a-1)]a>1时=1+1/aa1所以原式=1+1/a=(1+3*根号3)/(1+2*

a^2-a-1=0a²=a+1原式=[(a-1)(a+1)/a(a+1)-a(a-2)/a(a+1)]×(a+1)²/a(2a-1)=(a-1+a²+2a)/a(a+1)