👤
Rotarustefi
a fost răspuns

Demonstrati ca [tex] \frac{1}{k(k+1)} [/tex] = [tex] \frac{1}{k} [/tex] - [tex] \frac{1}{k+1} [/tex]

Răspuns :

Albastruverde12
[tex]\displaystyle \frac{1}{k(k+1)}= \frac{(k+1)-k}{k(k+1)}= \frac{k+1}{k(k+1)}- \frac{k}{k(k+1)}= \frac{1}{k}- \frac{1}{k+1} . [/tex]

Alte intrebari