Tính hợp lí:
A = 1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128
C = 22/3 . 32/2.4 . 42/3.5 ... 592/58.60
D = 6/1.3 + 6/3.5 + 6/5.7 + ... + 6/2009.2011
E = \(\frac{1.2.3+2.4.6-3.6.9+5.10.15}{1.3.7+2.6.14-3.9.21+5.15.35}\)
F = (1+1/2).(1+1/3).1+1/4)...(1+1/100)
G = 5 - 52/1.6 - 52/6.11 - ... - 52/101.106.