nguyenphuongmai.3011 1/18/2024 7:18:38 AM
tính nhanh: A= 1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128
B = 3/2+3/4+3/8+.........+3/128
C= 6/5+6/10+6/20+6/40+............+6/640
D= 1/3+1/9+1/27+1/81+.......+1/2187
E= 1+1/5+1/25+1/125+.........+1/15625