đặt biểu thức là A ta có :
A = 1/2 + 1/4 + 1/8 + 1/16 +1/32 +1/64 +1/128 + 1/256 + 1/512 + 1/102
A x 2 = 1+ 1/2 + 1/4 + 1/8 + 1/16 +1 /32+1/64 + 1/ 128 + 1/256 + 1/512
A = ( 1 + 1/2 +1/4 + 1/ 8+ 1/16 + 1/32 + 1/64 + 1/128 + 1/256 + 1/512 ) - ( 1/2 + 1/4 + 1/8 +1/16 +1/32 + 1/64 + 1/128 +1/256 +1/512 +1/1024)
A = 1 - 1/1024
A = 1023/1024
nhớ k nhé
(1 / 2) + (1 / 4) + (1 / 8) + (1 / 16) + (1 / 32) + (1 / 64) + (1 / 128) + (1 / 256) + (1 / 512) + (1 / 1024) =
0.9990234375
A=1/2+1/4+1/8+1/16+1/32+1/64+1/128+1/256+1/512+1/1024
a*2=1+1/2+1/4+1/8+1/16+...+1/512
a*2-a=1+1/2+1/4+...+1/512-1/2-1/4-1/8-/...-1/1024
a=1-1/1204
a=1023/1024
A=1/2+1/4+1/8+1/16+1/32+1/64+1/128+1/256+1/512+1/1024
2A = 1+1/2+1/4+1/8+1/16+...+1/512
2A - A = 1+1/2+1/4+...+1/512-1/2-1/4-1/8-/...-1/1024
A=1-1/1204
A=1023/1024
k đúng cái nhé
1/2+1/4+1/8+..................+1/2024 = 1-1/2+1/2-1/4+1/4-18+.............+1/512-1/1024 = 1-1/1024 = 1023/1024
