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《同学眼中的我》作文600字 函数f(x)=x^2-2x的单调减区间是 α,β是锐角,sinα=4/5cos(α+β)=5/13,求sinβ? 俄罗斯总统到底多长时间一届?为什么梅德韦杰夫和普京交替了,因为他们都出自于克格勃吗? 《行人和熊》的寓意是什么（文章在补充说明里）两个朋友一起上路,他们遇到了一头熊.一人抢先爬上树,藏了起来.另一人不及躲避只好倒在地上.据说熊不碰死的东西,在他跟前闻了又闻,他屏 补充说明的这句话是什么意思?茅元仪曰；「陈思王豪于文者也,而其自叙手搏,旨哉津津乎!今之介幷,反耻而不言,搓哉!末之难已? 看补充说明All members of the family go out to visit their relatives and friends on the first day of the new year. 已知cos2=4/5,cos（α+β）=3/5,且α,β均为锐角,则sinβ=多少 ___ all the students ___(get)the books?Yes,every student___(get)a book 翻译 students in primary and high schools------free exercise books by the chinese government everyyear(offer) 请问many student's books 和 many students' books哪个对?为什么? 这句话是什么意思（见问题补充说明）Have you ever noticed any English around you We belive you know KFC.That`s it!List as much as you can here,whatever you know． 形容一件事情做得非常棒,超出人的意料,用一个字来形容,用什么字最好? 拟人句十句 ｛x-y=3 2x+3(x-y)=11 用加减消元法解方程组 翻译!句子请看补充说明i was totally incorrect. i thought china was right above australia. but you are a lot further west of us.i'm very disapointed in myself. I like to think that i know where countries are我想知道深层含义 不光是 表现莲坚贞\纯洁\清高等品质的诗句其他的品质也可以,不要《爱莲说》里面的. 表明自己清廉正直纯洁的诗句（ ） 古代用一个字形容高兴的字是什么? He has a great sports collection.怎么译? 连词成句 brother a has sports my great collection 已知关于x的方程x²+（2k+1)x+k²=2的两根的平方和为11,求k的值 四个字的形容词人际关系. is englishi she a at school teacher an(连词成句） only的翻译 “只有用这种方法你们才能学好英语.”翻译用only开头 讨论函数的定义域f(x)=2x^3+3x^2-12x的单调性. 内切两圆的半径分别为R1、R2,两圆的圆心距O1O2=5.若R1、R2为方程x^2+kx+b=0的两根,求k值RT 若r1,r2是方程x+px+8=0的两个不等实根,则|r1+r2|的取值范围是? Not only does my brother like reading but also he likes playing sports 这个句子有毛病吗? Does your brother a member of the reading club No,he do not like reading.改错 百度输入法待选词语上面这个钻石什么意思?