题目内容
计算:8(72+1)(74+1)(78+1)(716+1)(732+1).
考点:平方差公式
专题:
分析:根据代数式的性质:乘以(7-1),在除以6结果不变,可化成平方差的形式,根据平方差公式,可得答案.
解答:解:原式=
•(74+1)(716+1)(78+1)
=
(72-1)(72+1)(74+1)(78+1)(716+1)(732+1)
=
(74-1))(74+1)(78+1)(716+1)(732+1)
=
(78-1)(78+1)(716+1)(732+1)
=
(716-1)(716+1)(732+1)
=
(732-1)(732+1)
=
(764-1).
| (7+1)(7-1)(72+1) |
| 6 |
=
| 1 |
| 6 |
=
| 1 |
| 6 |
=
| 1 |
| 6 |
=
| 1 |
| 6 |
=
| 1 |
| 6 |
=
| 1 |
| 6 |
点评:本题考查了平方差公式,乘以(7-1)除以6化成平方差的形式是解题关键.
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