(本题满分14分）已知函数. 当时，①求函数的单调区间； ②求函数的图象在点处的切线方程； 若函数既有极大值，又有极小值，且当时， 恒
如右图所示，打开止水夹，将液体A滴入试管②中与固体B接触。 若试管①中导管口有较多气泡产生，则液体A和固体B的组合不可能是
已知f(x)＝，给出以下几个结论： ①f(x)>0的解集是{x|0<x<2}；②f(－)是极小值，f()是极大值；③f(x)没有最小值，也没有最大值；④f(x)有最大值，没
After the workers had all gained the new skill, the factory produced ______ dolls in 2012 as the year before. A. more than twice as many B. twice as many as
某化学小组围绕燃烧与灭火的主题开展了相关活动。请你参与完成： 【知识回忆】可燃物燃烧的必备条件是
A football match between Class Two and Class Three ________tomorrow afternoon. A. is held B. was held C. must be held D. will be held
关于闭合电路的性质，以下说法正确的是 A．电源短路时，输出电流无限大 B．电源断路时，路端电压无限大 C．外电路电阻越大，输出
Today, roller skating is easy and fun. But a long time ago, it wasn't easy at all. Before 1750, the idea of skating didn't exist. That changed because of a man named Joseph Merlin. Merlin's work was m
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中，无理数的个数是（ ）