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(1)填空:(a-1)(a+1)=______ (a-1)(a2+a+1)=______  (a-1

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(1)填空:(a-1)(a+1)=______ (a-1)(a2+a+1)=______  (a-1)(a3+a2+a+1)=______(2)你发现规律了吗?请你用你发现的规律填空:(a-1)(an+an-1+…+a2+a+1)=______
(3)根据上述规律,请你求42012+42011+42010+…+4+1的值.
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3
(1)填空:(a-1)(a+1)=______ (a-1)(a2+a+1)=______  (a-1
根据题意:(1)(a-1)(a+1)=a2-1;
(a-1)(a2+a+1)=a3-1;
(a-1)(a3+a2+a+1)=a4-1;
(2)(a-1)(an+an-1+an-2+…+a2+a+1)=an+1-1.
(3)根据以上分析(1)42012+42011+42010+…+4+1299+298+297+…+4+1,
=
1
3(4-1)(42012+42011+42010+…+4+1),
=
1
3(42013-1).
故答案为:(1)a2-1,a3-1,a4-1;(2)an+1-1;(3)
1
3(42013-1).