椭圆的两个顶点A（-1,0）,B（1,0）,过其焦点F（0,1）的直线L与椭圆交于两点CD,并与X轴交与点P当椭圆的两个顶点A（-1,0）,B（1,0）,过其焦点F（0,1）的直线l与椭圆交于两点CD,并与X轴交与点P当绝

椭圆的两个顶点A（-1,0）,B（1,0）,过其焦点F（0,1）的直线L与椭圆交于两点CD,并与X轴交与点P当椭圆的两个顶点A（-1,0）,B（1,0）,过其焦点F（0,1）的直线l与椭圆交于两点CD,并与X轴交与点P当绝
椭圆的两个顶点A（-1,0）,B（1,0）,过其焦点F（0,1）的直线L与椭圆交于两点CD,并与X轴交与点P当
椭圆的两个顶点A（-1,0）,B（1,0）,过其焦点F（0,1）的直线l与椭圆交于两点CD,并与X轴交与点P当绝对值CD等于二分之三倍根号二时,求直线l的方程

椭圆的两个顶点A（-1,0）,B（1,0）,过其焦点F（0,1）的直线L与椭圆交于两点CD,并与X轴交与点P当椭圆的两个顶点A（-1,0）,B（1,0）,过其焦点F（0,1）的直线l与椭圆交于两点CD,并与X轴交与点P当绝
采用椭圆标准方程
椭圆的两个顶点A（-1,0）,B（1,0）=>a^2=1
焦点F（0,1）=>b^2-a^2=1 =>b^2=2
椭圆方程:x^2+y^2/2=1
直线L过(0,1),可设直线l的方程为
(y-1)=kx =>y=kx+1
代入椭圆方程
x^2+(kx+1)^2/2=1
=>(1+k^2/2)x^2+kx-1/2=0
=>(2+k^2)x^2+2kx-1=0 （1）
设CD两点坐标为(x1,y1)(x2,y2),x1,x2为方程（1）的两个根.
|CD|=√[(x2-x1)^2+(y2-y1)^2]=√(1+k^2)|x2-x1|=√(1+k^2)×√[(x1+x2)^2-4x1x2]
=√(1+k^2)×√[(2k/(2+k^2))^2+4/(2+k^2)]=3√2/2
=>(1+k^2)×(4k^2+8+4k^2)=(9/2)×(2+k^2)^2
=>[(1+k^2)/(2+k^2)]^2=9/16
=>k^2=2
=>k=±√2
直线方程为y=±√2x+1

Source: Qiqihar News ,cheap griffey shoes where is the old clothes of the "final destination" Li Weijing days ago In order wardrobe, cabinets full of old clothes, face heart trouble: the clothes of...

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Source: Qiqihar News ,cheap griffey shoes where is the old clothes of the "final destination" Li Weijing days ago In order wardrobe, cabinets full of old clothes, face heart trouble: the clothes of good quality, but just out of date style, I do not know to whom to give it away? In fact, every season, many people will issue such a feeling: cabinet full of old clothes as tasteless, leaving no place to place, throw another bear. 7 11-13, the reporter visited more than twenty members of the public found that as living standards improve,new ken griffey shoes, people clothes out faster and faster,king griffey shoes, because the old clothes and give birth to trouble really a lot of people, we are old clothes of the last "end" and a headache. Worry: a lot, but I want to wear clothes Open the wardrobe to wear real clothes for each season will then sets the rest are lying quietly in the corner. Speaking of their own wardrobe, shopping, beauty and love after 80 people, said Zhao Yuan, their daily shopping in the right love to see the total discount stores to buy two, you can buy some clothes back into the closet after forgetting to wear, to be the coming year, finishing wardrobe only to find label style is outdated, but still, those who pass through the old clothes to wear only one two seasons. with Zhao Yuan, like to work for three years [Wang told reporters that she recently put together a large number of school and the first job to buy clothes,women griffeys, throw a pity, wanted to donate to, but she did not know where you can receive such donations. She pointed to a neatly stacked pile of clothes a little depressing: "Look at this, our school,air griffey max 1 Fresh water, when the Games open hair, I pass through time, or new. Is it really only as a garbage disposal?" advocating low-carbon environment The regulations to reporters just a small account: If you throw away these clothes, they are an energy-consuming processing, a poor family will get donations to buy similar clothes factory clothes is an energy, in her words: "throw away the old clothes and unscientific,kids griffey shoes, not environmentally friendly." Well, count the hearts of this "small accounts" Wang stand firm: "Although I have not found good sources and methods to deal with these clothes, but Im certainly not a lost of." In the interview, the reporter also found that the old clothes,jordans heels, "output" is also the largest number of children. Members of the public who lives in the East Market district, said Miss Shi,air griffey max 1 black, daughter is only 4 years old, but clothes than their husband and wife are more, many have not had time to wear clothes on the smaller, these piles of old clothes I do not know how to deal with do. Choice: old clothes, "destination" Hard to Find talked about the handling of old clothes, many people say,griffey shoes, past practice,ken griffey shoes, there are two, one is sent to relatives, the second is organized in donations. 40-year-old Miss Gao Limei, said before the package can show it to rural relatives and old clothes to wear, but now improved living standards in rural areas, people also want to jump on the bandwagon, these outdated clothes and no one had rare. A few years ago, old clothes can also donate to the disaster area, may not know why in recent years, very few units of the organization donated clothes. Weapon: proposed the establishment of recycling facilities then, a growing number of residents in old clothes over how to dispose of? With the publics questions, the reporter interviewed the Municipal Civil Affairs Bureau. Municipal Civil Affairs Bureau Du Xuejun Deputy Director of Disaster Relief, said: "The public can donate old clothes washed, the civil affairs departments at all levels, civil affairs departments will give people a receipt issued by the appropriate, and then put these clothes were stored in a disaster relief warehouse, once necessary, will be allocated to the needs of victims. " the reporter found that some members of the public to donate clothes to this single approach does not agree,nike heels shoes, most of them want the old clothes can also be" material some value. " Reporters found that access to information, foreign clothes market has been relatively healthy, in Japan there are more than 2,ken griffey shoes,000 second-hand clothing stores, shopkeepers on the shops personal survival optimistic attitude, but also set up a trade association, with annual sales is over $ 200 million. Wear second-hand clothes, buy second-hand clothing is also very popular in the U.S. and European markets, Hong Kong,nike air max nm, there are also many second-hand clothes store monopoly star. In interviews, many people said the markets lack of clothes led to an enormous waste of energy, the city might also set up some specialized clothing collection company,ken griffey jr shoes, public house site to collect old clothes,ken griffey sneakers, pick out some secondary sales, the other part to recycle. Today, employment has become another major problem, to prepare the public may wish to start recycling old clothes in the starting brain teasers.

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直线方程为y=±√2x+1