已知多項式x平方-2x+3，當x=時，其最大值為.

x平方-2x+3
=（x-1）²；+2
當x= 1時，其最小值為2
最大值是∞

RELATED INFORMATIONS

1. 若點（x，y）滿足x²；+y²；-6x-4y+12=0.則x/y的最大值和最小值分別是？ x²；+y²；的最大值和最小值分別是？x+y的最大值和最小值分別是？
2. 如果關於x的不等式（a-1）x＜a-1的解集是x＞1，那麼a的取值範圍是（） A. a＞1B. a≥1C. a＜1D. a≤1
3. 已知數列{an}中a1＝1，點（an，an+1）在函數y＝3x+2的圖像上（n∈N*）.（I）證明：數列{an+1}是等比數列；（Ⅱ）求數列{an}的前n項和.
4. 設二維隨機變數（x，y）的聯合概率密度函數為：f（x，y）={2；0＜y＜x＜1 0；其他（1）求x，y的邊緣密度函數Fx（x）和Fy（y）（2）問x與y是否相互獨立
5. 已知f（x）=（m-1）x2+mx+1是偶函數，則f（x）在區間[-2，1]上的最大值與最小值的和等於______.
6. 已知函數f（x）=4x*2--kx 8若函數為R上的偶函數，求實數k的值
7. 幾何畫板怎麼讓兩條線段組合？我作了兩條相交線段但是發現一次只能移動一條線段，怎麼把它們合為一個整體
8. 初二幾題：正方形ABCD中角PAD=角PDA=15度，證明三角形PBC是正三角形
9. 一個二次函數的影像經過abc三點，點a的座標為（-1,0），點b的座標為（4,0），點c在y軸的正半軸上，且ab=oc. （1）求c點的座標；（2）求這個二次函數的解析式，寫出他的對稱軸；
10. 把12顆棋子放在8個方格裏，使上下左右加起來都等於5怎麼做 8個方格，指的是把一個正方形，平均分成9份，中間的那個格不要，只取其餘的8個格
11. 1.圓柱有兩個面是（）的圓，叫作圓柱的（）.2.圓柱的表面積包括（）和（）.
12. 27×99+27怎麼用簡便計算
13. 求二重積分D:X方+Y方在極座標下求。
14. 這樣到底是怎麼化簡的，背後的公式是…？（1-a∧2）-1/1-a=[（1-a∧2）*（1-a）-1]/1-a 然後又怎麼變成{a[（a-1/2）∧2-5/4}/1-a
15. 25分之18乘16分之9加25分之7乘16分之9加16分之9，脫式計算
16. 抛物線的問題焦點S（-1,1）準線y=x-2求方程這個抛物線不是上開口或下開口或左開口或右開口.它是斜著的，求高人指導，）
17. 一般現在時與現在進行時練習用一般現在時或現在進行時填空 1.Miss Guo（teach）us Chinese thisterm.She（be）a very goodteacher.Sheoften（talk）withher.Now，she（talk）with Lily. 2.Listen！Who（read）English？Han Meimeiis.Sheoften（read）English in the evening. 3.Where（be）Tom and Jim？They（play）football. LinTao（play）footballs too？No，he（mend）his bike. 4.Where their father（work）？He（work）on afarm.Butnow he（not work）.He（stay）at home. 5.What time the shop（close）？It（close）at nine o'clock in the evening. 6.He（go）to school by bus every day. 7.Tom can not walk fast because he（carry）a heavy box. 9.Why is the girl（stand）at the door？（ask）her to come in. 10.It's latespring.Theweather（get）o'clock and warmer.
18. 英語一般現在時，一般將來時，現在進行時練習
19. 一般現在時與現在進行時練習習題在下麵 He is standing under the tree.（對畫線部分提問）__________is he __________？ I am reading English.（改為一般疑問句）；__________you __________English？ He is watching TV now.（改為否定句）He __________ __________TV now.（改為否定句） I often have a good time.（改為現在進行時）I __________ __________a good time. He doesn’t do his homework.（改為現在進行時）He __________ __________ __________his homework. The children are drawing pictures.（對畫線部分提問）_______ __________the children __________？ There are some hills over there.（改為一般疑問句）__________ __________ __________hills over there？ He often cleans the blackboard after school.（用now改為現在進行時）；He ______ ______the blackboard now. ；1.The students are singing in the classroom.（對畫線部分提問）_____ _____the students ______in the classroom？ 16 The farmers are working over there.（改為一般疑問句）__________the farmers __________over there？ 18.Miss Gao is making the bed.（對畫線部分提問）__________ __________making the bed？ 22.They are having lunch.（對畫線部分提問）What __________ __________ __________？ 25.Ann doesn’t do her homework at home.（改為肯定句）Ann __________her homework at home. ； 27.Michael often reads newspapers after meals.（用now改寫句子）Michael ____ ______newspapers now. 四、用所給動詞的適當形式填空. 1.Look！They __________（write）on the blackboard. 2.Because the traffic __________（be）bad，I’m late. 3.He often __________（watch）TV in the evening with his wife. ； 4.----What’s he doing？---- He __________（study）English. ；
20. 一般現在時和現在進行時練習題答案 1.My mother often A eat B.eats C.eating 2.My aunt sometimes A.sing B.sings C.singing 3.Jack usually grandpa very much.A.miss B.misses C:missing 4.He _______his homework now.A:doing B.is doing C.does 5.Lily _________the piano now.A:playing B plays C is playing 6.Look！Tom __________in the sea now.A:swim B:swimming C:is swimming 7.Listen！The students __________now.A:cry B:are crying C cries 8.A bird every day.A.flies B.fly C.is flying 9.The horses often A .run B.runs C.is running 10.You A.dance B.dances C.are dancing 11.He to church on Sundays.A go B .goes C is going 12.Mom A show B.shows C.is showing 13.She A.watches B.watch C is watching 14.They _________the mountain every day.A:climbs B:climb C is climbing 15.Don’t shout！She ________now.A:sleeping B is sleeping C sleeps 16.He ________the picture now.A is painting B paints C is painting 17.Look！He _________now.A dance B is dancing C dances 18.My parents A.take B.takes C.are taking 19.That elephant two big ears.A.have B.has C.are D is A washes B.is washing C.wash 21.I __________a letter in the mail box now A putting B am putting C put 22.I ________a fairy tale now.A read B am reading C reads