cad画斜线的垂直线

英语句型：It'safternoon right now 问题；为什么要加个right在这里是什么意思 大学的微积分主要讲什么 I’ll get someone to check it right now为什么这里check前要加to 第三题 Last Sunday we went to a place_____they had never paid a visit before.这个空填什么啊? we came to a place to which they had never paid a visit before怎么解释用to which不能用where?关系副词where引导的地点状语从句和介词+关系代词引导的定语从句什么时候可以互换,什么时候不能?which要在分句 Last Sunday,they arrived at the farm ____they had never paid a visit before.A that BLast Sunday,they arrived at the farm ____they had never paid a visit before.A thatB whichC to whichD on which 手机电池厂里的a品和b品是什么意思 u=x^y x=f(t),y=g(t) 求du/dt 怎样使∫tf(x^2-t^2)dt(上限x,下限0)=1/2∫f(u)du（上限x^2,下限0) 倒数第一题怎么做,详细点 club meetings are on tuesdays and fridays 这句话对吗 club meetings are on Tuesdays and Fridays.这句话有错吗 双曲线方程中,P为抛物线上一点PF1+PF2等于什么?抛物线方程是什么? 已知双曲线X^2-Y^2 /2=1,过点p(1,1)能否作一条直线L,与双曲线交于A,B两点,且点P为线段AB的中点?用点差法对于一楼。很遗憾的告诉你。答案是不可以 已知双曲线y^2-X^2/2=1,过点p（1,1）能否作一条直线l,于双曲线交于A,B两点,且点p是线段AB的中点 已知双曲线x^2-1/2y^2=1,过点P(1,1)能否做一条直线l,和双曲线交于A,B两点,并且过P是线段AB的中点? 考试成绩太低卷子又要家长签字怎么办啊 数学期中考了11啊 怎么办啊啊啊啊啊啊啊啊 怎么给三年级孩子考卷上签字怎么给三年级孩子考卷(5科平均97分）上签字,不少20字,多谢 因式分解:32-2x的四次方 如图,已知OD、OE是∠COB的角平分线,且∠DOE=90°,试问OA、OB在一条直线上吗AOB是一条直线A----O----B Lucy often ___(help) her mother ____(do) housework I often help my mother ______ the washing.A.doing B.does C.do D.did 国内生产总值的年平均发展速度 《天时不如地利》中的几道题目,请快一点了!在线等!原文：天时不如地利,地利不如人和.三里之城,七里之郭,环而攻之而不胜.夫环而攻之,必有得天时者矣,然而不胜者,是天时不如地利也.城非 概率论的填空题,设X与Y是随机变量,且E（X）=E（Y）=1,D(X)=D(Y )=4,E(XY)=2,则D(2X-3Y+1)=?答案是40,应该是不难的题目, 求下列函数的导数 1) y=(4—3x)^9 2) y=x^2·sin^4·x 求会微积分的大神 He often helps his mother ____ housework over the weekend.A.do B.does C.did D.doing 改错 They begin theri class at forty past seven every day kitty has a caryon.She can draw.为什么选has和can Kitty has a crayon.She can draw.为什么选has和can 积分：（sin t）^2 dt＝∫（sin t）^2 dt＝