Đặt A=1/2+1/4+1/8+1/16+1/32+1/64+1/128+1/256
A=1/21+1/22+1/23+1/24+1/25+1/26+1/27+1/28
1/2A=1/22+1/23+1/24+1/25+1/26+1/27+1/28+1/29
A-1/2A=(1/2+1/22+1/23+1/24+1/25+1/26+1/27+1/28)-(1/22+1/23+1/24+1/25+1/26+1/27+1/28+1/29)
1/2A=1/2-1/29
A=2(1/2-1/29)
A=1-1/28
A=28-1
1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128 + 1/256 + 1/512 + 1/1024 = ???
KẾT QUẢ LÀ PHÂN SỐ TỐI GIẢN
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 = ?
Tính nhanh tổng sau:
1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128 + 1/256 + 1/512 + 1/1024
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
1/2+1/4+1/8+1/16+1/32+1/64+1/128+1/256+1/512+/1024
