[中學] 100中山女中教甄
想請教一題
找出所有的正整數n使得
(17/2)^n + (23/2)^n 是整數
我先用17=20-3和23=20+3展開
但不知該怎麼做下去?
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06/13 19:02, , 1F
06/13 19:02, 1F
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06/13 19:04, , 3F
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