(a-2/a²-2a - a-1/a²+4a+4)÷ a-4/a+2其中a满足a²+2a+1=0

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(a-2/a²-2a - a-1/a²+4a+4)÷ a-4/a+2其中a满足a²+2a+1=0

(a-2/a²-2a - a-1/a²+4a+4)÷ a-4/a+2其中a满足a²+2a+1=0
(a-2/a²-2a - a-1/a²+4a+4)÷ a-4/a+2
其中a满足a²+2a+1=0

(a-2/a²-2a - a-1/a²+4a+4)÷ a-4/a+2其中a满足a²+2a+1=0
a²+2a-1=0
a²+2a=1
原式=[(a-2)/a(a+2)-(a-1)/(a+2)²]×(a+2)/(a-4)
={[(a-2)(a+2)-a(a-1)]/a(a+2)²}×(a+2)/(a-4)
=(a²-4-a²+a)(a+2)/[a(a-4)(a+2)²]
=(a-24)(a+2)/[a(a-4)(a+2)²]
=1/(a²+2a)
=1/1
=1

数学就是要多练习哦,这是中考的必考类型题目,还有就是对分解因式、通风、约分要很熟悉哦。希望你加油哦

a²+2a+1=(a+1)^2=0
a=-1
代入上式
(a-2/a²-2a - a-1/a²+4a+4)÷ a-4/a+2
=(-3+2+2-4+4)÷ (-5)/1
=1/(-5)
=-1/5