作者LPH66 ( )
看板Math
标题Re: [中学] 解方程式一题请教
时间Fri Jul 18 18:54:48 2025
※ 引述《ccccc7784 (龙王号)》之铭言:
: 题目如下,先谢谢各位老师
: 除了硬爆开以外)
: https://i.imgur.com/fayAQLT.jpeg
照你令的 a = x-y, b = y-z, c = z-x, 所求为 -ab
自 a+b+c=0 乘以 2024 减去第一式得 2a+b=0
第一式乘以 2024 减去第二式得
2022*(2024-2022)*a + 2023*(2024-2023)*b = -2022
2022*2*a + 2023*1*b = -2022
把 b = -2a 代入
2022*2*a - 2023*2*a = -2022
a*(4044-4046) = -2022
-2a = -2022, a = 1011, b = -2022
所求为 -ab = 2044242 (或看选项的个位, 答案个位应为 1*2 = 2 故选 (B))
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因为所求是 -ab 没有 c, 所以上面消项把 c 消掉, 这样就剩下 a, b 好做了
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※ 编辑: LPH66 (123.194.181.180 台湾), 07/18/2025 18:55:44