[tex] 1 \frac{1}{2} * 1 \frac{1}{3} * 1 \frac{1}{4} * .. * 1 \frac{1}{99} * 1 \frac{1}{100} =
\frac{3}{2} * \frac{4}{3} * \frac{5}{4} * .. * \frac{100}{99} * \frac{101}{100} =
= 101/2 (s-au simplificat toti termenii in afara de primul si de ultimul) [/tex]