[3n(n+1)+n(n+1)(2n+1)]/6+n(n+2)化简
化简(n+1)(n+2)(n+3)
化简:1/(n+1)(n+2)+1/(n+2)(n+3)+1/(n+3)(n+4)
证明(1+2/n)^n>5-2/n(n属于N+,n>=3)
m-{n+3n-[8m-(5n+2n)+3} 化简
证明不等式:(1/n)^n+(2/n)^n+(3/n)^n+.+(n/n)^n
如果正整数n使得[n/2]+[n/3]+[n/4]+[n/5]+[n/6]=69,则n=
如果正整数n使得[n/2]+[n/3]+[n/4]+[n/5]+[n/6]=69,则n为( ).([ n ]表示不超过n
lim 9^n+4^n+2/5^n-3^2n-1 n趋于无穷大时
若n为正整数,求(3^n*2^n*5^n)/(-30)^n的值
初一计算:(m+5n)(m-n)-6(m+2n)(n-3n)?
化简:根号下1*5*10+2*10*20+n*5n*10n分之1*2*3+2*4*6+n*2n*3n