A = 2002 2000.16 − 1970 = 2002 ( 2002 − 2 ) .16 − 1970 = 2002 2002. ( 16 − 1 ) = 1 15
và B = 12.3 + 2.4.6 + 4.8.12 + 7.14.21 1.3.6 + 2.6.12 + 4.12.24 + 7.21.42 = 12.3 + 2.4.6 + 4.8.12 + 7.14.21 1.3.2.3 + 2.6.3.4 + 4.12.3.8 + 7.21.14.3 = 12.3 + 2.4.6 + 4.8.12 + 7.14.21 3. ( 12.3 + 2.4.6 + 4.8.12 + 7.14.21 ) = 1 3 = 5 15
Vậy B > A