2a+3*0.8a+5*0.8*0.8a=38怎么解
(a+3a+5a+...+2009a)-(2a+4a+6a+...+2008a)=
(a+3a+ 5a+```+2007a)-(2a+4a+6a+```+2008a)=?
(a+3a+5a+...+2013a)-(2a+4a+6a+...+2012a)=
先化简,再按要求将化简结果重新排列a*a+3a*a*a*b*b*b-[2a*a*b+0.8ab*ab-a*a*a
(5A+2A-3-4A)-(-A+3A-A)其中A=-2
玩悠悠球时,1A,2A,3A,4A,5A怎么玩.
3(a-7)+5(a-4)=15怎么解
5a+(2–4a)=0怎么解
a=2*3,a*5此表达式怎么理解
a+a^2+a^3+a^4+a^5+a^6...+a^n=a^n+1-a/a-1 (a-1)≠0
当a=1时,a-2a+3a-4a+5a…+99a-100a=
化简 a-2a+3a-4a+5a'''''''+99a-100a a=-2 的值