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若不等式|2a‐1|≤|x+1∕x|对一切非零实数X恒成立,则实数a的取值范围 对于x属于R,不等式|2-x|+|1+x|≥a^2-2a恒成立,则实数a的取值范围为 -Have you heard the song Super Star?-Yes,I hear it sung by S.H.E. Have you heard the song 《You and Me》?Yes,l heard it【】by sarah brightman.A sing B sung应该是heard sb do sth 做完后 校对了下答案 还是本就选这个,要给理由 -----Have you heard the song Super Star?-----Yes,I heard it ____by S.H.E.A.singB.sung Have you heard of( )about Jeremy Lin?Yes.He did quite well in the last NBA basketball match.A anything exciting B something interesting C anything humorous D something important -Have you heard of the buildings_down?-Yes,it's said that they are going to make room for the new ones.-A:having pulled B:having been pulled C:pulled D:to be pulled 问一道比较纠结的物理题电阻越并越小,电压表的电阻很大,相当于断路,如果有足够的电压表和导线,将电压表并联,能不能让一盏与之混联的电灯电阻10欧姆发光,用的电压表是学生在实验室用 Perhaps you have heard ___ about the Interneet (A:a lot B:lots of C:a few D:a little of)为什么? Have you heard about the Prime Minister? 求函数y=lx-3l+lx+1l的最大值和最小值 求2+lx-3l的最小值,求2-lx-3l的最大值 没几道的 .选择 1.两个力作用在杠杆两端,为了使杠杆两端保持平衡,则（）A.这两个力大小必相等 B.这两个力的力臂长短必相等 C.力臂较长的那个力必大 D.力臂较长的那个力必小2.用扳手拧生 在浓度为20%的盐水中加入30千克水,浓度变为15%,再加入几千克盐,浓度变为25%? 向浓度为15%的盐水中加入25克盐,这时盐水的浓度时多少? 在浓度为百分之十五的盐水中,再加入25克盐,这时盐水的浓度是（百分之（ ） 在浓度为20％的盐水中加入10千克水,浓度变为15％,再加入多少克盐,浓度变为25％?要一步步来解释,不要用字母和方程,用的公式打出来, 若y=x-1的绝对值+x+1的绝对值,则y的最小值是多少 我的高中物理有点困难 How deep I love I love have eyes for you 啥意思 我是72年生的到今年我年龄多大了? 填空,就一个空, 谁能帮我填上这个空?（是根据首字母填空的题）并把空里填的词的意思告诉我,A:I want to join the chess club.B:Can you play chess?A:Yes,I can.B:Can you play w_____?A:No,I cann't. 按意思填空,每空一词.1.这个周末一起踢足球怎么样?whai about ____ ____ together this weekend?2、在回家的路上,我遇见了一位老朋友.i met an old friend ____ ____ ____ ____.3.她昨天骑自行车去上学了.she _____ __ 检查一下,顺便告诉我空着的怎么写 have what I need to te.i love you deep in my heart. thank you什么意思 根据答语填空,完成下面每组对话的问句部分,每空一词~1（ )the( )by your watch?Let me see.Oh,it's ten to eight.2( ) ( )your son go to school every day?On foot.3( ) ( ) those socks?They’re Army's.4（ ）did you say sorry to your have what I need to te.i love you deep in my heart.thank My love is deep as the sea .The more I give to you ,the more I have. 函数(1/2)^√-x²+x+2的定义域和值域分别是? 凑24：（1）1,6,6,8. （2）2,7,9,10. （3）5,6,7,9. （4)2,5,6,9.