求[(1*2*4+2*4*8+…+n*2n*4n)/(1*3*9+2*6*18+...+n*3n*9n)]^2
求[(1*2*4+2*4*8+…+n*2n*4n)/(1*3*9+2*6*18+...+n*3n*9n)]^2
1\n(n+3)+1\(n+3)(n+6)+1\(n+6)(n+9)=1\2 n+18 n为正整数,求n的值
跪求;(1*2*4+2*4*8+.n*2n*4n/1*3*9+2*6*18+.n*3n*9n)的平方.
证明不等式:(1/n)^n+(2/n)^n+(3/n)^n+.+(n/n)^n
lim 9^n+4^n+2/5^n-3^2n-1 n趋于无穷大时
(1*2*4+2*4*8+……+n*2n*4n/1*3*9+2*6*18+……+n*3n*9n)^2
(1*2*4+2*4*8+……+n*2n*4n)÷(1*3*9+2*6*18+……+n*3n*9n)
计算【(1*2*4+2*4*8+...+n*2n*4n)/(1*3*9+2*6*18+...+n*3n*9n)】的2次方
计算:(1*2*4+2*4*8+...+n*2n*4n)/(1*3*9+2*6*18+...+n*3n*9n)
化简:1/(n+1)(n+2)+1/(n+2)(n+3)+1/(n+3)(n+4)
(n+1)(n+2)/1 +(n+2)(n+3)/1 +(n+3)(n+4)/1
求极限 lim(n->无穷)[(3n^2-2)/(3n^2+4)]^[n(n+1)]