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[函数] 看到绝对值就绝望之二

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lrh2006 Posted at 2020-7-17 08:54:27 |Read mode

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色k Posted at 2020-7-17 10:09:52

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realnumber Posted at 2020-7-17 11:03:28
Last edited by realnumber at 2020-7-17 17:41:00$f(x)=(x+\frac{a}{2})^2-m,m=-1+\frac{a^2}{4}$,
令$x+\frac{a}{2}=x_0=t-0.5$
以下两个不等式要同时成立,即不等式组有解
$-0.25\le  (t-0.5)^2-m \le0.25$,--------(1)
$-0.25\le  (t+0.5)^2-m \le0.25$,---(2)
1.当m〈0.25时,分别解得t的范围,
2.当m≥0.25时,

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 Author| lrh2006 Posted at 2020-7-17 12:52:02
谢谢两位,不过还是不太明白
参考答案有两种方法
答案1.jpg
答案2.jpg

或者:
答案3.jpg

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 Author| lrh2006 Posted at 2020-7-17 12:57:24
Last edited by lrh2006 at 2020-7-17 13:07:00图片太大,我不知道怎样让它变小
然后这两个参考答案我也看不懂

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 Author| lrh2006 Posted at 2020-7-17 13:10:58
请各位帮我解释一下,谢谢谢谢!

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2025-4-21 14:11 GMT+8

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