照你令的 a = x-y, b = y-z, c = z-x, 所求為 -ab
自 a+b+c=0 乘以 2024 減去第一式得 2a+b=0
第一式乘以 2024 減去第二式得
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
所求為 -ab = 2044242 (或看選項的個位, 答案個位應為 1*2 = 2 故選 (B))
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因為所求是 -ab 沒有 c, 所以上面消項把 c 消掉, 這樣就剩下 a, b 好做了
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※ 編輯: LPH66 (123.194.181.180 臺灣), 07/18/2025 18:55:44
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