已知a2+2a-1=0,求(a-2/a2+2a - a-1/a2+4a+4)÷a-4/a+2的值

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已知a2+2a-1=0,求(a-2/a2+2a - a-1/a2+4a+4)÷a-4/a+2的值
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已知a2+2a-1=0,求(a-2/a2+2a - a-1/a2+4a+4)÷a-4/a+2的值
已知a2+2a-1=0,求(a-2/a2+2a - a-1/a2+4a+4)÷a-4/a+2的值

已知a2+2a-1=0,求(a-2/a2+2a - a-1/a2+4a+4)÷a-4/a+2的值
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

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