Question

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上面是解答，但我不知道怎麼解！！求救

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9. 令滿足不等式3≤4x+7≤7之最大整數為M,最小整數為m,
則M+m=

Answer 1

✨ 最佳解答 ✨

綾

3 ≤ | 4x + 7 | ≤ 7
=> -7 ≤ (4x + 7) ≤ -3 or 3 ≤ (4x + 7) ≤ 7
=> -7/2 ≤ x ≤ -5/2 or -1 ≤ x ≤ 0
M = 0
m = -3