1 Tính
A = 1+52+54+....................+5200 , B = 3-32+33-34+.....................+399-3100
C = \(\frac{1}{7}+\frac{1}{7^2}+.................+\frac{1}{7^{100}}\)
D = \(-\frac{4}{5}+\frac{4}{5^2}-\frac{4}{5^3}+..................+\frac{4}{5^{200}}\)
E = 63+64+..............................+6150