先化简,再求值:a²-1/a²-2a+1÷a+1/a³-a²,其中a=根号3

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先化简,再求值:a²-1/a²-2a+1÷a+1/a³-a²,其中a=根号3

a²-1/a²-2a+1÷a+1/a³-a²
=(a+1)(a-1)/(a-1)²÷(a+1)/a²(a-1)
=a²
=(√3)²
=3

(a²-1)/(a²-2a+1)÷(a+1)/(a³-a²)
=(a+1)/(a-1)*a^2(a-1)/(a+1)
=a^2
当a=√3 时,
a^2=3

[(a²-1)/(a²-2a+1)]÷[﹙a+1﹚/﹙a³-a²﹚]
=[(a-1)(a+1)/﹙a-1﹚²][a²﹙a-1﹚/﹙a+1﹚]
=a²
当a=√3 则a²=3