E = 1/2 + 1/4 + 1/8 + 1/16 + ...... + 1/128 + 1/256
S=1/2+1/4+1/8+1/16+...+1/128+1/256 = ?
Tính:
A= 1/2+1/4+1/8+1/16+1/64+1/128+1/256
e =1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128 + 1/256
1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128 + 1/256
1/2+1/4+1/8+1/16+1/32+1/64+1/128=1/256
1/2+1/4+1/8+1/16+1/32+1/64+1/128+1/256 = ?
1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128 + 1/256 + 1/512
Tính nhanh : 1+1/2+1/4+1/8+1/16+1/32+1/64+1/128+1/256+1/512
