【文章內(nèi)容簡(jiǎn)介】 = .若 。在ΔABC中，已知AB=2，BC=3，CA=4，則cosA= 已知向量 若向量 在ΔABC中，若sinA=，BC=4，則AB= 用一儀器對(duì)一物體的長(zhǎng)度重復(fù)測(cè)量5次，得結(jié)果（單位:cm）如下： 1004，1001，998，999，1003； 則該樣本的樣本方差為 cm2. .設(shè) 三、解答題在已知點(diǎn)P（0,）到拋物線拋物線的方程，并求拋物線上到點(diǎn)P的距離為的點(diǎn)的坐標(biāo)。拋物線坐標(biāo)原點(diǎn)，若直線OA、OB的斜率之和為1，求直線的方程假設(shè)兩個(gè)二次函數(shù)的圖象關(guān)于直線x=1對(duì)稱，其中一個(gè)函數(shù)的表達(dá)式為y=x2+2x－1,求另一個(gè)函數(shù)的表達(dá)式。三個(gè)正數(shù)成等差數(shù)列，和為15，若將這三個(gè)數(shù)分別加上1，4，19后，得到的三個(gè)數(shù)成等比數(shù)列，求這三個(gè)正數(shù)。已知已知等差數(shù)列 （I）求數(shù)列的通項(xiàng)公式； （II）當(dāng)n為何值是，數(shù)列的前n項(xiàng)和取得最大值，并求該最大值。已知函數(shù) （I）求m的值； （2）求函數(shù)已知 （I）∠B的正弦值；（II）ΔABC的面積。已知雙曲線的中心在原點(diǎn)，焦點(diǎn)在x軸上，離心率等于3，并且經(jīng)過點(diǎn)（－3，8），求： （I）雙曲線的標(biāo)準(zhǔn)方程； （II）雙曲線的焦點(diǎn)坐標(biāo)和準(zhǔn)線方程。數(shù)學(xué)答案一、選擇題 二、填空題 3 13 5. 6 6. 7. 6 8. 9.10. 三、解答題解 因?yàn)椤螦=60176。，BC=由正弦定理得 即 所以 =解 設(shè)0）上任意一點(diǎn)，有 d===當(dāng)由已知得 解得所以a=5不合題意，舍去當(dāng)a=1時(shí)，有x2=1所以x=177。1，y=1故所求拋物線方程為y=x2,所求點(diǎn)為（－1，1）和（1，1）解 設(shè)A、B的坐標(biāo)分別為分別為kk2，則： 把 故 所以直線解 設(shè)點(diǎn) 點(diǎn)P（代入方程①得 化簡(jiǎn)得,即為所求解 設(shè)成等差數(shù)列的三個(gè)數(shù)分別為根據(jù)已知條件列方程組 由①得a=5將a=5代入方程②，并整理得 解此方程得 所以 所求的三個(gè)數(shù)是8解 因?yàn)? 解：（I） 設(shè)等差數(shù)列 （II）數(shù)列的前項(xiàng)和 == 解：（I） 所以函數(shù)解：（I）由已知，BC邊在x軸上，AB邊所在直線的斜率為1，所以∠B=45176。 因此 (II) ΔABC的面積S=解：（I）設(shè)所求雙曲線的焦距為2c，標(biāo)準(zhǔn)方程為，由已知所以 由因此所求雙曲線的標(biāo)準(zhǔn)方程為（II）由（I）知a=1,c=3，可知雙曲線的焦點(diǎn)坐標(biāo)為（－3，0）和（3，0），準(zhǔn)線方程為英 語一、語音知音在下列每組單詞中，選出劃線部分與其他單詞的劃線部分讀音不同的選項(xiàng)。二、詞匯與語法知識(shí)從每小題的四個(gè)選擇項(xiàng)中，選出最佳的一項(xiàng)，并把它前面的大寫字母填入左邊的括號(hào)里。 （ ） spent traveling around the world by bike.A．a(chǎn) year and a half B. one year and halfC．a(chǎn) year and one half D．one and half year（ ） don’t think this film worth again. see B. to be seen C. seeing D. being seen（ ） person I spoke just now is the manager that I told you about. which who whom（ ）4. exciting city New York is! an much（ ）5.—I usually go to work by bus. —Why not by bike for a change? to go going try going go（ ）6. More than 90 percent of the watches on sale ourselves. made of made up of made by made by（ ） asked Gray are you travelling were you travellingB. where are you travelling to he was travelling（ ） lot of buildings and the place very noisy ever since we moved here. been built。 has bee built 。has beeB. have been built。 became built。 became（ ） 2300 years ago, there lived a greater thinker Aristotle. named name（ ） talked at the top of his voice, he drew nobody’s attention.（ ）11 the post office. I saw a lot of people buying newspapers and magazines.（ ） night I the letter for you. post be posted（ ） brother is five years than I.。 older。 old。 old。 elder（ ） are only two assistants in that shop.。 shoe。 shoe。 shoes。 shoes（ ） is interested in English. He often works at it until into the night.。 deep。 deeply。 deeply。 deep（ ） girl is not to dress herself. enough old old strong（ ） face suggested that he at the news.。 be excited 。 was excitedB. exciting。 is excited。 was excited（ ） goes to work every day Saturday and Sunday.( ） are held at the club twice a month.’s’ of（ ）20. His bike badly. The worker it now. damaged。 is repairing damaged。 has repaired。 repaired damaged。 will repair（ ） have forgotten the date I met him last time.（ ） to the post office and don’t forget the parcel with you go 。 to take。 taking。 to take go。 taking（ ）’m sorry for being late. My car on the highway.A. turned down down out off（ ） was in that big room I saw the great man. which（ ） like watching TV than seeing a film. better better better more（ ）26. number of students in our university increasing year by year.。 is 。are。 are 。is ( ） years have passed he left his motherland.（ ）. Smith be in the office now. I saw him take a taxi just a moment ago.’t’t’t’t（ ） night I found a boy crying in the street. years old old（ ） in the past three years? you gone you gone you go you been（ ）31. the old man walks! slow slowly slow slowly（ ） you read the book, you’d better make a mark you have any questions. which where place where（ ） we boys were working hard in the garden, our sisters themselves in the sitting room. enjoyed enjoying enjoy（ ） is third largest country in area in the world.C./( ） country has own customs.’s（ ）36. the children for me when I am away, will you? up at into after（ ） Kennedy was of the United States. president thirty – fifth president thirty fives president D. president the thirtiethfive（ ）38. a teacher, I should set a good example to the students. been be I being（ ） is said Mr. Smith visited our school last week. some （ ） river is 70 meters wide. Can you swim it? （ ）41. We found the room not big enough so