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

RELATED INFORMATIONS

• 1. 求二重積分D:X方+Y方 在極座標下求。
• 2. 27×99+27怎麼用簡便計算
• 3. 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（）.
• 4. 已知多項式x平方-2x+3，當x=時，其最大值為.
• 5. 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？
• 6. 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
• 7. 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.
• 8. 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
• 9. 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______.
• 10. 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
• 11. 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
• 12. 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，）
• 13. 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.
• 14. 英語一般現在時，一般將來時，現在進行時練習
• 15. 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. ；
• 16. 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
• 17. 現在進行時練習 句型轉換： 1.They are doing housework .（分別改成一般疑問句和否定句） _____________________________________________________________ _____________________________________________________________ 2.The students are cleaning the classroom .（改一般疑問句並作肯定和否定回答） _________________________________________________________________ _________________________________________________________________ 3.I’m playing the football in the playground .（對劃線部分進行提問） _________________________________________________________________ 4.Tom is reading books in his study .（對劃線部分進行提問） _________________________________________________________________ 3和4題畫線部分不知道了，我在學習現在進行時，請畫線再回答.
• 18. 求英語現在進行時練習答案，【英語天才進】 一.寫出下列動詞的現在分詞形式 work_______sing_______play___ __study_______ have _______dance ________write___ __take________ run_________sit_________shop________swim__________ lie________ 二.按要求改寫句子 1.The boy is playing basketball. 否定句：____________________________ 一般疑問句：_________________________ 肯定回答：______________________否定回答：______________________ 對“is playing basketball”提問：__________________________ 對“The boy”提問：__________________________ 2.They are singing in the classroom. 否定句：____________________________ 一般疑問句：_________________________ 肯定回答：____________________否定回答：______________________ 對“are singing”提問：__________________________ 對“in the classroom”提問：__________________________ 三.用現在進行時完成下列句子 1.What _________you __________（do）？2.I _____________（sing）an English song.3.What ________he ____________（mend）？ 4.He ______________（mend）a car. 5.______you __________（fly）a kite？Yes，_____________. 6.______she ___________（sit）in the boat？ 7.______you _____________（ask）questions？ 8.We _______________（play）games now. 9.What are you _________（do）now？I ___________（eat）bread. 10.It’s nine o’clock.Myfather_______________（work）in the office. 11.Look，the boy____________（put）the rubbish into the bin. 12.__________he__________（clean）the classroom？No，he isn’t.He____________（play）. 13.Where is Max？He___________（run）on the grass. 14.Listen，who____________（sing）in the music room？ Oh，Mary_____________（sing）there. 1.Who _____over there now？ A.singing B.are sing C.is singing D.sing 2.It’s eight o’clock.Thestudents _____an English class. A.have B.having C.is having D.are having 3.Listen！The baby _____in the next room. A.crying B.cried C.is crying D.cries 4.Look！The twins _____new sweaters. A.are wearing B.wearing C.are wear D.is wearing 5.Don’t talkhere.Grandparents_____. A.is sleeping B.are sleeping C.sleeping D.sleep 6.Tom is aworker.He____in afactory.Hissisters _____in a hospital. A.work/ work B.works/ work C.work/ works 7.Who _____English best in your class？ A.speak B.speaks C.speaking 8.Mrs.Read_____the windows every day. A.is cleaning B.clean C.cleans 9.We _____music and often _____to music. A.like/ listen B.likes/ listens C.like/ are listening 10.She _____up at six in the morning. A.get B.gets C.getting 11.On Sundays he sometimes _____his clothes and sometimes _____some shopping. A.wash/ do B.is washing/ is doing C.washes/ does 12.The twins usually _____milk and bread for breakfast，but Jim _____ some coffee for it. A.have/ have B.have/ has C.has/ have
• 19. 英語語法練習題【現在進行時 一、連詞成句.並作出四種形式. 1、play，school，at，student，the，football，be 肯定句： 否定句： 問句： 回答： 2、mother，her，her，tell，stories，be 肯定句： 否定句： 問句： 回答： 3、drink，milk，you，be，now 肯定句： 否定句： 問句： 回答： 4、friend，my，listen，park，music，to，the，in，now，be 肯定： 否定： 問： 答： 5、my，father，go，fishing，be，now 肯定： 否定： 問： 答： 6、girl，the，her，wash，clothes，be 肯定： 否定： 問： 答： 7、the，read，book，English，his，be，now，boy 肯定： 否定： 問： 答： 8、they，their，fix，be，bathroom，sink，now 肯定： 否定： 問： 答： 都是現在進行時.
• 20. 現在進行時和過去進行時練習題及答案