97×98×99×100+1=n×n,n等于几

97×98×99×100+1=n×n,n等于几 (n+1)^n-(n-1)^n=? 推导 n*n!=(n+1)!-n! 已知an为等差数列且a1+a2+`````+a100=A,a(n-99)+a(n-98)+````+a(n-1)+an=B(n>100,n属于N*)则Sn=答案为[(A+B)n]/200 9题 = 101 (n+1)!- = n*n!n(n+1)!- n*n! f(x)=e^x-x 求证(1/n)^n+(2/n)^n+...+(n/n)^n 证明:(n+1)n!= (n+1)! 为什么 [ln(n)]'/n'=1/n 当n为正偶数,求证n/(n-1)+n(n-2)/(n-1)(n-3)+...+n(n-2).2/(n-1)(n-3)...1=n (n)(n+1)分之1+(n+1)(n+2)分之1……(n+99)(n+100)分之1 化简 2n*1/2^n=n/2^(n-1)? 阶乘(2n-1)!=（2n)!/(2^n*n! f(n)=(n+1/n)^n 求导 为什么n!/(2!(n-2)!)=n(n-1)/2! Sn=n(n+2)(n+4)的分项等于1/6[n(n+2)(n+4)(n+5)-(n-1)n(n+2)(n+4)]吗? 高数题：n趋近于0,lim｛1/（n^2+n+1)+2/(n^2+n+2)+3/(n^2+n+3)+.+n/(n^2+n+n)｝=? (1+n)n=240 for(n=1;n