Question

化简1/2!+2/3!...+n-1/n!(n属于自然数,n大于等于2)

Answer 1

由 1/(n-1)!- 1/n!= n/n!- 1/n!= (n-1)/n!可知有等式 (n-1)/n!=1/(n-1)!- 1/n!所以 1/2!+2/3!+3/4!+...+(n-1)/n!1/1!-1/2!+1/2!-1/3!+1/3!-1/4!+.+1/(n-1)!-1/n!=1-1/n!