题干

已知曲线C的极坐标方程是ρ=1,以极点为原点,极轴为x轴的正半轴建立平面直角坐标系,直线l的参数方程为x=1+
t
2
y=2+
3
2
t
为参数).
(1)写出直线l与曲线C的直角坐标方程;
(2)设曲线C经过伸缩变换x'=2xy'=y得到曲线C′,设曲线C′上任一点为M(x,y),求x+23y的最小值.
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答案(点此获取答案解析)

解:(1)直线l的参数方程为x=1+t2y=2+

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You Can Fly More Frequently

    When traveling, airfare can take up a large part of your travel budget. What if you could fly practically for free? If it were possible, then you would probably travel more, right?____ While it may seem like a lot of work to accumulate miles, it's pretty easy when you know how.

    Sign up for mileage (里程) programs. You can't gain miles if you don't sign up.____ Pick one or two airlines that you use most often and try to bring all your points into those programs by flying with them.

    Buy gifts and have dinner out. Most mileage programs have a business list where you can register several credit or debit cards and then earn miles for each purchase you make through their participating shops or meal you have at restaurant partners.____so why not make it count toward future travel?

    Use your credit card. Look for a card that gives you rewards. There are a ton of credit card companies that offer mileage cards that give you miles for each dollar you spend. Use it for bills, groceries, gas and anything else you would normally use your bank account for and then pay it off at the end of the month.____

    Rent a car. Whenever you rent a car, you have the choice to include your frequent flyer member number.____ but it can be more beneficial to pay less than a dollar a day to earn one or more miles per dollar spent on your rental.

A. Some will charge a fee

B. With frequent flyer programs, you can

C. You're probably doing these things anyway

D. It's an easy way to accumulate miles and can add up really fast

E. In fact, you can get a free plane ticket just focusing on certain ones

F. Join frequent flyer programs, so you can start accumulating those miles

G. There are plenty of ways to earn money just by doing things you're already doing

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阅读下文,回答问题

菊事

丁立梅

    ①去年冬天,我把一盆开过花的菊,随手丢弃在屋旁,连同装它的瓦盆。

    ②屋旁有巴掌大的空地,没人理它,它便自作主张地在里面长婆婆纳,长狗尾巴草,长车前子,长蒲公英,还长荠菜。我挑过一回荠菜,满像那回事的,把一份野趣挑进篮子里。后来,这一小撮荠菜,被我切碎了,烙进糯米饼里。饼烙得金黄,配了糯米的糯白,配了荠菜的嫩绿,不用吃,光看看,就很享受了。咬一口,鲜透牙。很是感动了一回,有泥土的地方,总会生长着我的故乡。

    ③现在,这块地里,多出一大丛的菊来。是被我丢弃的那一盆。谁想到呢,它的花萎了,叶萎了,心竟是活的。它搂着这颗心,落地生根,不声不响地,勤勤勉勉地生长。最终,它不单自己活了下来,还子孙满堂的样子,——去冬不过一小瓦盆的花,今秋已繁衍成一大丛了。它让我想到柳暗花明,想到天无绝人之路,想到苦尽甘来,只要心没有死,总有出头之日的。

    ④风一场,雨一场,秋季翻过,已是冬了,它还没开够,朵朵灿烂。满世界的萧条,唯它,一簇新亮,是李商隐诗里的“融融冶冶黄”,是童年乡下屋檐下的那抹明黄,打老远就看得见。路过的人,有的站着远远瞅,有的看不过瘾,走近了细细瞧。一律的惊叹,好漂亮的花!它倒是沉得住气,面对众人的赞赏,不动声色,不慌不忙地,只管把好颜色往外掏。一瓣金黄,再一瓣,还是金黄。如历尽世事的女子,参透人生无常,倒让自己有了一份坚守,那就是,守住自己,守住心。所以,冷落也好,繁华亦罢,它都能安然相待,不急不躁。

    ⑤孤寡老人程爹,在小区的小径旁种菊。小径旁的空地,原是狭长的一小块,小区人家装修房子,把一些碎砖碎玻璃倒在里面。路过的人都小心不去碰触,以免被玻璃划伤了。连调皮的小猫,也绕着那块地走。老人清理掉碎砖碎玻璃,在里面种青菜和菊。几棵青菜,几朵菊花。再几棵青菜,几朵菊花。绿配紫,绿配红,绿配白,绿配黄,小块的地,让人看过去,竟有花园般的感觉。

    ⑥这些天,老人除了吃饭睡觉,几乎都围着他的菊在转。我上班时看见他,下班时还看见他,背着双手,很有成就感地在小径上漫步,来来回回。一旁,他的菊,如同被惯坏的孩子,正满地打着滚,撒泼似的,把些紫的、红的、白的、黄的颜色,泼洒得四处飞溅。哪一朵,都是硕大丰腴的,都上得了美人头。

    ⑦天冷,菊越发的艳丽,直艳到人的心里去。小区的人,每日里行色匆匆,虽是久住,彼此却毫不关己地陌生着。而今,因为这些菊,一个个舒缓了脚步,脸上僵硬的线条,渐渐柔软起来。话搭话地闲聊几句,说着花真好看之类的。或者不聊,仅仅站着,看一眼菊,相互笑笑,自有一份亲切,入了心头。再遇见.便是老相识了。清寒疏离的日子,因菊,变得脉脉温情。

(选自《扬子晚报》)