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理论力学的一道题目,求约束力的大小 五年级下学期数学书p141-142答案 ··· 人教版的书p141-142的 新人教版五年级下册数学书142页有什么题? 设数列an是等差数列,a1 已知数列{an}是等差数列,且a1+a2=4,a7+a8=28,则S10=? Flashing back to the character as a young man...的结构Flashing back to the character as a young man helps the andience get used to Kutcher in the role结构是什么样的? 已知集合A={1,3,-x3},B={1,x+2},是否存在实数x,使B∪（CaB）=A?若存在,求集合A和B. 已知集合A=《1,3,-x2》,B=《1,x+2》,是否存在实数x,使得B∪（CaB）=A? A={1,3,-x的三次方},B={x+2,1}是应存在实数x,使B⊆A,若存在,求出集合A,B 把my father is warching TV in the room.改成否定句 在平行四边形中,BC=2AB,CA垂直于AB,求角B和角CAD的度数 What's the____of the word?(mean) you must walk into the room____.(quiet) 在平行四边形ABCD中,AB=3,BC=5,CA⊥AB,E为AB上的一定点,且AE=1,F为动点. 当F点在BC线段上时,BF=?△EBF为等腰三将形；当F在AD线段时,AF=?时,△BEF为等腰三角形 在平行四边形ABCD中,CA⊥AB,∠BAD=120°,BC=10cm ,则AC=____,平行四边形ABCD的周长是——. We must keep quiet and walk___out of the room A.We must keep quiet and walk___out of the room A.quiet B.quick C.quietly D.quite 在等差数列[an]中：d=负3分之1,a7=8 求a1 等差数列an中,d＝-3,a7＝10,则a1 星星为什么闪 6.I share a bedroom with my sister.My sister and I __________ in the __________ room. my （ ） sister is living with a student from sydney我妹妹和一个来自悉尼的学生住在一起 I went to the beach with my sister (对my sister提问) ( )7.I with my sister _______ TV.A.are watch B.are watching C.am watching D.is watching i ()one room with my sister.为什么用share peter walked into the room____because his father was sleeping .a.quietly b.quickiy c.carefullyd.kindly 2.Mrs.White e________ the room quietly,because her baby was sleeping.3.She kept on _______（举） her hand.4.He made some toys______________（please)his little son.5.They ___________ (talk)about the leture when I came in.6.His dog ___________(lie) 星星为什么闪 英语连词成句 blue.father.is.in.the.my.man急用 甲乙两辆汽车分别从ab两地相向开出,甲车每小时行42千米,乙车每小时行54千米.甲,乙两车第一次相遇后仍按原速继续前进,各自到达对方出发地点后立即按原路返回.两车从开出到第二次相遇共 四年级开心暑假答案甲乙两车同时从ab两地相对开出,甲车每小时行42千米,经过3小时相遇,求AB两地相距多少米要补充条件再解答的 n 个独立同分布的随机变量,知其均值和方差,运用切比雪夫不等式求P{u-4 已知集合A={1,3,x∧2},B={1,x+2},是否存在实数x,使得集合B是集合A的子集?若存在,求出集合A,B；若不存在,请说明理由 科普知识,真的有急用,快呀,我要做手抄报