题干

已知fx=x3+ax2+a+6x+1有极大值和极小值,则a的取值范围为(       )

A:-1<a<2

B:-3<a<6

C:a<-1或a>2

D:a<-3或a>6

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D

同类题3

阅读下面的文字,完成下列小题

酒酿王

凌鼎年

    黄阿二的酒酿在古庙镇上老老少少都翘起大拇指,没有不说呱呱叫的。古庙镇人黄、王不分,大伙习惯喊黄阿二为“酒酿黄”,但听起来总像“酒酿王”,其实喊他酒酿王倒也不虚不谬。至少在古庙镇上,还没有谁做酒酿能做得过黄阿二的。

    黄阿二做酒酿,不用大钵头,而是用小钵头。据说小钵头酒酿比大钵头酒酿难做,因此做酒酿小生意的,都***钵头,不敢轻易改用小钵头,单凭这一点,黄阿二就区别其他做酒酿买卖的。

    古庙镇人只要一听那吆喝就知道是“酒酿王”来了。别人喊“酒酿——酒酿来——”他喊“酒酿——小钵头甜酒酿来哉——”,酒酿王的嗓音很浑厚,有一种穿透力,能穿过门墙,撞入人们的耳膜。一年四季,春夏秋冬,都能听到酒酿王的吆喝,他那极有韵味的吆喝可以说已成了古庙镇的一种文化风景。

    古庙镇的人偏好吃酒酿有些年头了,来了客,端碗酒酿小圆子,乃待客的一种,既不破费多少,也还上得台面,那些老吃客十有八九认准酒酿王的酒酿。据他们说,一上口就能吃出是不是酒酿王做的酒酿。每每这时,黄阿二脸上就浮现出一种满足,一种得意来。用他的话说,有老吃客的这些评价,比吃人参还补。

    酒酿王的酒酿从来只有买不到的日子,没有卖不掉的日子。但黄阿二坚持每天只做三十小钵头,一小钵头也不多做,从无例外。通常他九点钟骑了黄鱼车笃悠悠地走街串巷,一路骑过去,一路吆喝过去。黄阿二常说:他做酒酿买卖,一半是为了能吆喝上这几声。只要每日里这么吆喝一嗓子,通体舒畅。若待在家里只吃不做,不吆喝,不出一个月保管憋出病来。

    黄阿二的酒酿常常是不到吃中饭就卖光了。下午,他或茶馆里坐坐,或澡堂城泡泡。天长日久,他有了不少茶友、浴友,每日里聚在一起,嚼起来没有啥话题避讳的。有位老茶友对他说:“你的酒酿,牌子已做出了,生意这么好,何不多做点?”“我只一双手。”黄阿二说了这话再不多言。有位浴友替他出主意说:“那请一两个帮手嘛,你还可过过老板瘾呢。”黄阿二默默半晌后说:“我这人命贱,自己不动手做,比死还难受。再说了,自己做放心。做好做坏,心里有底。”

    黄阿二的酒酿不论斤不论两,论钵头的,一小钵头一买,连钵头买也可,用锅用盆来倒回去也行。他的酒酿打出牌子,不挑不拣,顺着摆放的次序拿,若要比比看,挑挑看,他就不卖。老主顾都知道,黄阿二的酒酿钵钵一样,无需挑挑拣拣的,否则,咋叫“酒酿王”?古庙镇的人都说:如今像黄阿二这样信得过的生意人越来越少了。

    有次,一公司总经理来找他定做五十小钵头酒酿,说有批上海客户慕他酒酿王的名,点名要吃他酿的小钵头酒酿。公司准备连钵头买,钱可以预付。

    黄阿二说:“可以。但每天只有三十钵头,若要五十钵头只能分两天交货。”

    那怎么行。公司总经理表示价钱上可以提高点。

    谁知黄阿二说做五十钵头质量上就难保证了。只能一天三十钵头。要就要,不要拉倒,没啥商量的。

    经理碰了一鼻子灰,一百个想不通。有赚不赚猪头三,这黄阿二死脑子一个。

    听惯了黄阿二的吆喝,几回不听见,就有人问:“酒酿王这两天怎么没来?”往往这话还在耳边,那“酒酿——小钵头甜酒酿来哉——”的吆喝声就传来了。

    最近,连着好几天未听到酒酿王的吆喝声了,生活中仿佛缺了什么。一打听,原来黄阿二病了。大家怪想念黄阿二的,几个老茶友、老浴友结伴前去看望他。进了门,大伙儿一起吆喝了一声:“酒酿——小钵头甜酒酿来哉——”

    黄阿二听后浑身一震,他撑起身子说:“你们这一声吆喝,对我来说,比吃啥药都强,这不,毛病好了一半。”

(摘自《第五届小小说金麻雀奖获奖作品》,有删改)

同类题5

阅读理解

    “My dear lady,”says Holmes.“You're shivering.Are you cold? Do you want a cup of hot tea?”

    “I'm not cold,”the woman replies,“I fear for my life!”

    “We are here to help you.Don't worry about anything.I don't know you.But I know many things about you.For example,I know how you traveled.You came to London by train.You also rode to the train station on a horse—drawn wagon.''

    “Why,yes.You‘re right.But how do you know these things?”

    “I see a return ticket in your glove.I see fresh mud on the left arm of your dress. Now tell us your problem.''

    “My name is Helen Stoner,”she states,“My mother and father are dead.I am living with my stepfather.Dr.Grimsby Roylott.He comes from a rich family.But they are no longer rich.They have nothing except a small piece of land and a huge old house.We are living in the house. Dr.Roylott is using my mother's mone37 for expenses.Part of it was for my sister and me. It was for our marriages.”

    Holmes is sitting in his chair.His eyes are closed.He is listening carefully to Helen's story.He hears every detail.

    Helen continues. “My stepfather has no friends.He fights with everyone.He is strong and gets angry quickly. Everyone is afraid of him.”

    “He has no friends at all?”asks Holmes.

    “No.He talks to no one except the gypsies(吉普赛人).They are poor people who travel from place to place.A band of gypsies is staying on our land right now.''

    “Are you and your sister afraid of the gypsies?”

    “My dear Mr.Holmes.You are making me so sad.My sister is dead.That is why I am standing here in this room.”    ,  .