kill(all)$

fpprintprec:10$

van=facebook.com/LearningCalculus$

A(n):=fullratsimp((n+1)*sqrt(n)+n*sqrt(n+1))$

a(n):=fullratsimp(1/A(n))$
a(n);

'sum(a(n),n,1,99);

S:sum(radcan(a(n)),n,1,6);

S:sum(radcan(a(n)),n,1,99)$

bfloat(S);

float(%);