a-5-(2a-1)化简
化简; a-2a+3a-4a+5a-6a+``````-2006a+2007a.
化简:3a-[5a-(2a-1)]=
化简:(1-a)^2/a-1 (a
化简 3(-3a^2-2a)-[a^2-2(5a-4a^2+1)-3a]
化简:(3a-2a^2)-[5a-1/3(6a^2-9a)-4a^2].
当a=1/2+根号5时,化简9-6a+a^2/a-3加(根号下a^2-2a+1)/a^2-a
化简a(a+2)-(a-1)(a+1)
(a+2)(a-2)-a(a+1)化简
化简:|a-2|-|5-a|
化简:2(a+1)-a
化简 a-2a+3a-4a+5a'''''''+99a-100a a=-2 的值
(2a^2+3a+2)/(a+1)-(a^2-a-5)/(a+2)-(3a^2-4a-5)/(a-2)+(2a^2-8a