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[函数] 含参不等式又升级了 有什么办法吗

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facebooker Posted 2019-8-28 15:14 |Read mode
Last edited by facebooker 2021-9-19 23:171)若不等式$\frac{e^{\sin x}-a}{x+1}-\sin x+\ln (x+1)-1\geqslant 0$恒成立,则$a$的取值范围___

2)若对 $\forall x>0,a(e^x+1)\geqslant 2(x+\dfrac{1}{x})\ln x $恒成立,则整数$a$的最小值___

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力工 Posted 2019-8-28 15:52
回复 1# facebooker
这样的问题应该对太乐展开式有很好的理解吧.

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realnumber Posted 2019-8-29 07:35
第一题a 不见了
第2题不会

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 Author| facebooker Posted 2019-8-29 11:01
回复 3# realnumber

不好意思 现在有a了  模仿的2019浙江压轴风格

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realnumber Posted 2019-8-29 11:16
Last edited by realnumber 2019-8-29 11:33forum.php?mod=viewthread&tid=6519&extra=page=1
刚从这里的2楼学的
\[ \frac{e^{sinx}-a}{x+1}=e^{\sin x -\ln{(x+1)}}-\frac{a}{x+1}\ge 1+\sin x -\ln{(x+1)}-\frac{a}{x+1}\]
代回原不等式,可得$a\le 0$

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kuing Posted 2019-8-29 14:01
回复 5# realnumber

不错,学得够快
第二题我也不会,也懒得想太多,怕又是抄错题

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isee Posted 2019-8-29 15:02
回复 6# kuing

对你,仅仅对你,一般是前者不发生~

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 Author| facebooker Posted 2019-8-29 16:23
回复 6# kuing

都说题目有问题 有大佬这么说我就放心了

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realnumber Posted 2019-8-30 07:09
回复 8# facebooker

kk只说不会,猜测题目也许抄错,en,没说题目有问题.

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isee Posted 2019-8-30 17:01
回复 1# facebooker


用电脑画了下图,第(2)题可能是求整数 $a$ 的最小值.

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 Author| facebooker Posted 2019-8-31 04:27
回复 10# isee

高手就是不一样 确实是求整数a  这个咋做啊?

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kuing Posted 2019-8-31 12:08
果然又是抄错题

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