(a-3)(a+7)-(3a+7)(2a-1)化简
化简3a×a×a+12a×a-6a-12 a=根号7-1
(高一集合)已知A={2,4,a*a*a-2a*a-a+7},B={1,a+3,a*a-2a+2,a*a*a+a*a+3
(a 1)(a 2)(a 3)(a
1+2a+3a^2+4a^3+5a^4+6a^5+5a^6+4a^7+3a^82a^9+a^10
已知a^2+a+1=0,求1+a+a^2+a^3+a^4+a^5+a^6+a^7+a^8的值
已知1+a+a^2=0求1+a+a^2+a^3+a^4+a^5+a^6+a^7+a^8的值
求和:1,a+a^2,a^3+a^4+a^5,a^6+a^7+a^8+a^9,···(a不等于0)
化简(—a^3+3a^2-7a+5)+(5a^-6a)-(a^3-4a+7)
化简; a-2a+3a-4a+5a-6a+``````-2006a+2007a.
(a+1)(a+3)(a+5)(a+7)+15
3a平方-2a+4a平方-7a
(a-3)(a+7)-(3a+7)(2a-1)化简