先化简,在选择一个你喜欢的数代入求值 2011a/a²-2a+1÷(a+1/a²-1+1)
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先化简,在选择一个你喜欢的数代入求值 2011a/a²-2a+1÷(a+1/a²-1+1)
先化简,在选择一个你喜欢的数代入求值 2011a/a²-2a+1÷(a+1/a²-1+1)
先化简,在选择一个你喜欢的数代入求值 2011a/a²-2a+1÷(a+1/a²-1+1)
2011a/(a²-2a+1)÷[(a+1)/(a²-1)+1]
=2011a/(a-1)^2÷[(a+1)/(a-1)(a+1)+1]
=2011a/(a-1)^2÷[1/(a-1)+1]
=2011a/(a-1)^2÷a/(a-1)
=2011a/(a-1)^2×(a-1)/a
=2011/(a-1)
令a=2代入:
=2011/(2-1)
=2011
2011a/(a²-2a+1)÷[(a+1)/(a²-1)+1]
= 2011a/(a-1)²÷[(a+1+a²-1)/(a²-1)]
= 2011a/(a-1)²÷[a(a+1)/(a+1)(a-1)]
= 2011a/(a-1)²÷[a/(a-1)]
= 2011a/(a-1)...
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2011a/(a²-2a+1)÷[(a+1)/(a²-1)+1]
= 2011a/(a-1)²÷[(a+1+a²-1)/(a²-1)]
= 2011a/(a-1)²÷[a(a+1)/(a+1)(a-1)]
= 2011a/(a-1)²÷[a/(a-1)]
= 2011a/(a-1)²x(a-1)/a
=2011/(a-1)
令a=0,则
原式=2011/(0-1)=-2011
收起
化简的事你得自己做。
但是你得注意:在选择一个你喜欢的数代入时所有的分母不能为零
即a²-2a+1≠0
a+1≠0
a²-1
a+1/a²-1+1≠0
即a=1,a=-1,a=0都是不行的