1.______scientific attitude is needed in developing our city.I agree with you.In this way,we canmake_____mistakes.为什么要填More；fewer啊?2.Did you return Li Ming's call?I didn't need to_____I'll see him tomorrow.A.until B.unless C.when D.beca

1.______scientific attitude is needed in developing our city.I agree with you.In this way,we canmake_____mistakes.为什么要填More；fewer啊?2.Did you return Li Ming's call?I didn't need to_____I'll see him tomorrow.A.until B.unless C.when D.beca a与-a的大小关系有三种：1.a>-a；2.a=-a；3.a 计算：a²/a-1-a-1. 1.a 1.a 化简a(a+1)/1+(a+1)(a+2)/1.+(a+2009)(a+2010)/1 请你填出题中a所表示的数,使等式成立.1.a-a=a×a a=（ ）2.a×a=a÷a a=( ）3.a+a=a÷a a=( )4.a+a=a×a a=( ) 请填出题中A表示的数,使等式成立1.A-A=A*A A=( ) 2.A*A=A/A A=( ) 3.A+A=A/A A=( )4.A+A=A*A A=( )1/2表示啥意思.2不对吧 请填出题中a所表示的数,使等式成立1.a－a＝a×a a＝( ) 2.a×a＝a÷a a＝( ) 3.a+a＝a÷a a＝（ ) 4.a＋a＝a×a a＝( ) 根据乘方的意义:a的平方=a×a,a的立方=a×a×a.1.计算:a的平方×a的立方= 1.( -2/2a+3) + (3/3-2a)+[ 2a+15/ (2a-3)(2a+3)]2.[(a+2a^2-2a) - (a-1/a^2-4a+4)] ÷ 4-a/a 如果根号a三次方+a平方等于-a根号a+1.那么a的取值是 化简 (2a²-5a)-2(3a-5+a²),a=1... 先化简,在求值：(a-2) (a+2)-a (a-2),其中a=-1.全部 化简 (2a²-5a)-2(3a-5+a²),其中a=1... a分之a的绝对值等于1.a等于多少 因式分解：1.a²-2a2.（a+2)(a-2)+3a 3.a²-4 4.2a²-18 1.化简.（1）.【[(a+2)/(a^2-2a)]+[8/(4-a^2)]】/【（a-2）/a】