Chứng minh:
a, A = 1 + \(\frac{1}{2^2}\)+ \(\frac{1}{3^2}\)+ \(\frac{1}{4^2}\)+ ... + \(\frac{1}{100^2}\)< 2
b, B = 1 + \(\frac{1}{2}\)+ \(\frac{1}{3}\)+ \(\frac{1}{4}\)+ .... + \(\frac{1}{63}\)< 6
c, C = \(\frac{1}{2}\). \(\frac{3}{4}\). \(\frac{5}{6}\). \(\frac{7}{8}\).... \(\frac{9999}{10000}\)< \(\frac{1}{100}\)
GIÚP MÌNH VỚI NHÉ, MÌNH ĐANG CẦN GẤP LẮM