a+increasing+number+of
@钟单2568：An increasing number of people是“ 大量剧增的人”这个意思吗??后面一定用复数吗?? -
鱼詹18056237616…… 应该译为“越来越多的人”.a number of +n.复数形式,后面谓语动词对应的也是复数形式,区别于the number of +n复数形式,后者译为.“.. ...的数目是... ...”后面用单数的谓语动词.
@钟单2568：利用极限存在准则证明题目.怎么做? -
鱼詹18056237616…… a1=√2 for n>=2 an = √[2+a(n-1)] {an } is increasing an = √[2+a(n-1)] (an)^2 = 2+a(n-1) (an)^2 - a(n-1) - 2 =0 (an)^2 - an - 2 <0 (an -1/2)^2 < 5/2 √2 <an < (1+ √10)/2 {an} is bounded => lim(n->∞) an exists
@钟单2568：如何证明a1=1,an+1=3 - 1/an这个数列收敛并求极限 -
鱼詹18056237616…… consider f(x) = 3- 1/x f'(x) = 1/x^2 >0 f(x) is increasing a2 = 3-1/a1= 2 >a1=> {an} is increasing |an|=> lim(n->∞)an exists let L = lim(n->∞)an a(n+1)=3- 1/an L = 3- 1/L L^2- 3L +1=0 L = (3+√5)/2 lim(n->∞)an = L = (3+√5)/2
@钟单2568：With gas prices constantly increasing 随着油价的持续增长.这里 increase 为什么要用动名词形式呢? -
鱼詹18056237616…… 1、这里主要是涉及with+复合宾语的用法,一共有六种,你学到3A了?2、例句为其中的用法之一6)“with+名词+现在分词”: 如:The English class ended with all singing an English song.英语课以全体合唱一首英语歌而结束.(singing与with的宾...
@钟单2568：there be 句型否定句式的构成在be后加上not.也可用no来表示.即:no+n(名词)=not a/an/any +n(名词).注意:no+n(可数名词单数)=no a/an+n(可数... - 作业帮
鱼詹18056237616…… [答案] 后面打错了,应该是not a/an+n 例句There is a book on the desk. There is no book on the desk. There is not a/any book on the desk. 希望对你有所帮助.如满意请点击下面的“选为满意答案”按钮,
@钟单2568：已知数列{an}的通项公式an=n2+λn+2,若数列{an}为单调递增数列,则实数λ的取值范围是______. - 作业帮
鱼詹18056237616…… [答案] 解方法一: ∵an=n2+λn+2, ∴an+1=(n+1)2+λ(n+1)+2, ∵数列{an}为单调递增数列, ∴an+1-an=2n+λ+1>0(n∈N*)恒成立, ∴λ>-2n-1(n∈N*)恒成立, 令f(n)=-2n-1(n∈N*), 则λ>f(x)max=-2*1-1=-3 ∴λ>-3. ∴实数λ的取值范围是(-3,+∞). 方法二: ...
@钟单2568：数列{an}是一个单调递增数列,且an=n2+λn(n∈N*),则实数λ的取值范围是______. - 作业帮
鱼詹18056237616…… [答案] ∵an=(n+ λ 2)2− λ2 4是一个单调递增数列,∴− λ 2≤1,解得λ≥-2. 故答案为[-2,+∞).
@钟单2568：The+序数词+n和a+序数词+n有什么区别 ,有什么意思 -
鱼詹18056237616…… “The+序数词+n”表示特指“第几个”;“a+序数词+n”表示泛指“又一次”.
@钟单2568：初三英语:a+序数词+time 和the +序数词+time -
鱼詹18056237616…… 首先你题目抄错了,应该是-It's the third time for you to do this, but you failed again.-yeah,so I'd like to try a __time.A.the forth B. fourth C.the fourth D.a forth 答案选B.the+序数词 表示的是:第几,a+序数词+名词 表示的是 :又,再 上文的翻译是-这是你第三次做这了但是又失败了.-恩,所以我想再尝试一下.(try a fourth time 因为前面已经说了我已经做了三次,所以这地方是fourth) 希望你能体会明白
@钟单2568：英语造句①A+谓语+the最n in/of②A+谓语+one of the最+in③A+谓语+the 最+n,A,B,n,C造句,再加④A+谓语+序+最+n+of/n - 作业帮
鱼詹18056237616…… [答案] Amy got the highest grades in her class. She is one of the best dancers in team. I am the laziest boy.
鱼詹18056237616…… 应该译为“越来越多的人”.a number of +n.复数形式,后面谓语动词对应的也是复数形式,区别于the number of +n复数形式,后者译为.“.. ...的数目是... ...”后面用单数的谓语动词.
@钟单2568：利用极限存在准则证明题目.怎么做? -
鱼詹18056237616…… a1=√2 for n>=2 an = √[2+a(n-1)] {an } is increasing an = √[2+a(n-1)] (an)^2 = 2+a(n-1) (an)^2 - a(n-1) - 2 =0 (an)^2 - an - 2 <0 (an -1/2)^2 < 5/2 √2 <an < (1+ √10)/2 {an} is bounded => lim(n->∞) an exists
@钟单2568：如何证明a1=1,an+1=3 - 1/an这个数列收敛并求极限 -
鱼詹18056237616…… consider f(x) = 3- 1/x f'(x) = 1/x^2 >0 f(x) is increasing a2 = 3-1/a1= 2 >a1=> {an} is increasing |an|=> lim(n->∞)an exists let L = lim(n->∞)an a(n+1)=3- 1/an L = 3- 1/L L^2- 3L +1=0 L = (3+√5)/2 lim(n->∞)an = L = (3+√5)/2
@钟单2568：With gas prices constantly increasing 随着油价的持续增长.这里 increase 为什么要用动名词形式呢? -
鱼詹18056237616…… 1、这里主要是涉及with+复合宾语的用法,一共有六种,你学到3A了?2、例句为其中的用法之一6)“with+名词+现在分词”: 如:The English class ended with all singing an English song.英语课以全体合唱一首英语歌而结束.(singing与with的宾...
@钟单2568：there be 句型否定句式的构成在be后加上not.也可用no来表示.即:no+n(名词)=not a/an/any +n(名词).注意:no+n(可数名词单数)=no a/an+n(可数... - 作业帮
鱼詹18056237616…… [答案] 后面打错了,应该是not a/an+n 例句There is a book on the desk. There is no book on the desk. There is not a/any book on the desk. 希望对你有所帮助.如满意请点击下面的“选为满意答案”按钮,
@钟单2568：已知数列{an}的通项公式an=n2+λn+2,若数列{an}为单调递增数列,则实数λ的取值范围是______. - 作业帮
鱼詹18056237616…… [答案] 解方法一: ∵an=n2+λn+2, ∴an+1=(n+1)2+λ(n+1)+2, ∵数列{an}为单调递增数列, ∴an+1-an=2n+λ+1>0(n∈N*)恒成立, ∴λ>-2n-1(n∈N*)恒成立, 令f(n)=-2n-1(n∈N*), 则λ>f(x)max=-2*1-1=-3 ∴λ>-3. ∴实数λ的取值范围是(-3,+∞). 方法二: ...
@钟单2568：数列{an}是一个单调递增数列,且an=n2+λn(n∈N*),则实数λ的取值范围是______. - 作业帮
鱼詹18056237616…… [答案] ∵an=(n+ λ 2)2− λ2 4是一个单调递增数列,∴− λ 2≤1,解得λ≥-2. 故答案为[-2,+∞).
@钟单2568：The+序数词+n和a+序数词+n有什么区别 ,有什么意思 -
鱼詹18056237616…… “The+序数词+n”表示特指“第几个”;“a+序数词+n”表示泛指“又一次”.
@钟单2568：初三英语:a+序数词+time 和the +序数词+time -
鱼詹18056237616…… 首先你题目抄错了,应该是-It's the third time for you to do this, but you failed again.-yeah,so I'd like to try a __time.A.the forth B. fourth C.the fourth D.a forth 答案选B.the+序数词 表示的是:第几,a+序数词+名词 表示的是 :又,再 上文的翻译是-这是你第三次做这了但是又失败了.-恩,所以我想再尝试一下.(try a fourth time 因为前面已经说了我已经做了三次,所以这地方是fourth) 希望你能体会明白
@钟单2568：英语造句①A+谓语+the最n in/of②A+谓语+one of the最+in③A+谓语+the 最+n,A,B,n,C造句,再加④A+谓语+序+最+n+of/n - 作业帮
鱼詹18056237616…… [答案] Amy got the highest grades in her class. She is one of the best dancers in team. I am the laziest boy.
