(a^n+2)-(2a^n)+(3a^n-1) 因式分解a^（n+2)-2a^n+3a^（n-1)

a^n+2+a^n+1-3a^n因式分解 数列a(n)=n (n+1)(n+2)(n+3),求S(n) (3a^n+1+6a^n+2-9a^n)/3a^n-1 (6a^n+2 +3a^n+1 -9a^n)/3a^n-1 因式分解 a^4n+a^3n+a^2n+a^n -a^n-(-5a^n-1)-2(a^n-1-3a^n) (a^n+b^n)(a^2n-a^n*b^n+b^2n) 设a,n∈N*证明a^2n-(-a)^n≥(a+1)×a^n a^n+2-18a^n+81a^n-2 a^n+2+a^n+1-a^n因式分解 a^n+1+a^n-1-2a^n因式分解 a^(n+1)b^n-4a^(n+2)+3ab^n-12a^2因式分解 计算:(3a^n+2+6a^n+1-9^n)÷3a^n-1 如果n是正整数,[(8a^n+3)-(6a^n+2)-(5a^n+1)]/(-a)^n 1/3a^2n -(-7a^n)+(-1)^2n+1 a^n -(2/5a^2n)-5a^n(n为正整数） a^n+2-a^n的因式分解 因式分解:a^n+2-6a^n (a^n+1)-(a^n-2)等于