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他花了半个小时才走到书店.It took him half an hour _____ _____ _____ the bookstore. 1 36/(x-0.3)-36/x=42 x/7+72=7x-72 （要有步骤）X-7/4-5X+8/3=11/2(X-4)-(3X+4)=-15/2 It took them half an hour to get to the airport的同义句是什么? 因式分解：x^3-6x-40 (写出过程和方法,) 因式分解想x（6x-1）-1 因式分解x^4-6x^3+x^2+7 x-6x 7因式分解怎么分 试讨论函数f(x)=ax/(x^2一1),x(一1,1)的单调性(其中a不等于0) 运用“文化创新”的知识,说说如何提高创新能力 怎样答高中政治题 设a不等于0,试确定函数f(x)=ax/1-x2在（-1,1）的单调性. 帮我解一道数学一元二次方程!快 为什么cos3xcos2x=1/2(cos5x+cosx) 高中椭圆、双曲线、抛物线的问题有一本书上说：（1）平面上到两个定点的距离之和为定值的点的轨迹是椭圆或线段（2）平面上到两个定点的距离之差为定值的点的轨迹是双曲线或直线或 受古人的启发,你可利用许多小平面镜制作一种什么装置 太阳光与水平地面成30度角.为使光能照亮井底,请在图中作出平面镜,并计算出平面镜与水平面成多大角 that boy often s_____ his toys with the other children 动词填空：He often uses a computer______(help) with his work.还有 It is interesting______(make) different kinds of cakes. 1.My teacher often _____(招待)us as her children.2.He seems _____(be)happy with me.3.there are many clouds in the sky.It seems _____.(rain)4.Tom often knocks _____ the desk when he is angry. 解下面三角方程：(1)sinx＝cos3x (2)2sinxcosx＋sinx－cosx＝1 数学;关于x的一元二次方程mx的二次方-（3m-1)x+2m-1=0,若(3m-1）的二次方-4m（2m-1）=1,求m的值及该方程的根 儿童现代诗1首自编一定要是自编的 Teacher often__students to take their___.A.advice;advices B.advise;advices C.advise;advice D.advice;advice顺便说说他们的区别~ The children are waiting ___the bus stop ___their teacher.A.for;atB.at;forC.at;atD.for;for 已知 f(x) 是二次函数,且满足 f(0)=1 ,f(x+1)-f(x)=2x ,求 f(x) . 如何正确鼓励孩子孩子表现欲太强,如何让他正确凸显表现欲,是否在他最需要表现的时候,我们去鼓励他,夸赞他表现欲太强背后隐藏着什么?我们家长该如何改进,从而使孩子能够正视自己因为 给自己的小孩写鼓励信怎么写 如何正确表扬孩子 如何正确的表扬孩子? 将下列陈述句按括号内的内容变为强调句:1.(The children )often help their parents do the farm work.2.（In 1993）,a tomato was developed that was very different from any grown before. 一道英语连词成句Su Yang,Museum,bus,wanted,the,History,to,by