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she was born the morning August 18th 介词用什么 she was born the outskirts of MontrealA.on B.in C.at D.from 求函数y=4tan(x/2-π/5)的定义域和单调区间 已知函数y=(2的x次方 2的-x次方)除以2的定义域,值域已知函数求定义域,值域 求函数y=(x/2 + π/3)的定义域和单调区间 homas Edison was a famous American scientist .He was born in 1874 .When he was a child,he liked 二元一次方程3x-my=4和mx+ny=3有一个公共解x=1,y=-1,则m=?n=? Thomas Edison was a famous American science.根据短文的内容选择正确答案Thomas Edison was a famous American scientist.He was born in 1847.When he was a child,he liked to find out how things worked.He was in school for only three months.He born in American .Edison was a famous scientist and inventor .he had more than 1000 great intention 求翻译这篇文章加答案最好thomas edison was a famous american scietist 因式分解：8x(y-2x)+1-y^2快 因式分解：4(2x-y)^2-(2x+y)^2求过程rt,快啊! （a—7）² （b-9）=0求a,b是多少 European Born Chinese American-born Chinese怎么翻译 我知道ABC是America Born Chinese,那么,BBC是什么? Ameracan-born Chinese 与 Chinese born in American 一样吗 数学家的小故事10字 Edison is famous --- his over 1,000 inventions(发现） ,and he is famous --- a great inventor.A as;as B for;forC as; forD for;as Edison is a great inventor or Edison was a great inventor （a+b）×（a+b）=100,且a=7.5,求b的值是多少? 当|a|=5,|b|=7,且|a+b|=a+b,则a-b的值为? 方程3x的m-2平方+ny-y=5是关于x,y的二元一次方程,则m=（ ）,y=（ ） B/（A+2）＝7/9 B/（A+3）＝3/4 计算或化简:①√(-144)*(-9)②2√10*（-√40）③√8*√7*√14 化简——3/5:9/10 U=A∪B={1,2,3,4,5,6,7,8,9,10},A∩B={3,4,5},求B 数学家的故事40到60字,还要独一无二的 数学家的故事40字 如何尽快提高做数学题的速度和准确率呢总是觉的题目会做 但不是做的太慢就是准确率太低请指教. 怎样提高做数学题的速度和准确率还有三个月中考,但我做一张卷子要把时间做满且正确率低大概100分的题得70几分,120的题得90几分麻烦有此经验的同学或老师给点意见要自己试过的,不要去转 非常难的数学题,已知X和Y都是实数,且满足〔绝对值符号→〕｜X-5｜是这样的，只要哪个说了话，我创这个号是为了帮人家耍分值的，哪个要分，