3(1/2+1/4+1/8+1/16.....1/128)
A=(1/2+1/4+1/8+1/16....1/128)
2A-A=A
2A=(1/2+1/4+1/8....1/128)*2
=1+1/2+1/4....1/64
2A-A=1+1/2+1/4+1/8....1/64-(1/2+1/4+1/8......1/128)
A=1-1/128=127/128
Đáp số:3*127/128=381/128
3(1/2+1/4+1/8+1/16.....1/128)
A=(1/2+1/4+1/8+1/16....1/128)
2A-A=A
2A=(1/2+1/4+1/8....1/128)*2
=1+1/2+1/4....1/64
2A-A=1+1/2+1/4+1/8....1/64-(1/2+1/4+1/8......1/128)
A=1-1/128=127/128
Đáp số:3*127/128=381/128
Tính nhanh
a) 1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128 + 1/256
b) 1/3 + 1/9 + 1/27 + 1/81 + 1/243 + 1/729
C=3/2+3/4+3/8+3/16+...+3/128
D=1/2+1/4+1/8+...+1/1024
E=5/2+5/8+5/32+5/128+5/512+5/2048
C=3/2+3/4+3/8+3/16+....+3/128
E=5/2+5/8+5/32=5/128+5/512+5/2048
Cần gấp giúp mik với
tính nhanh: 3/2+3/8+3/32+3/128+3/52
Tính nhanh: 3/2 + 3/8 + 3/32 + 3/128 + 3/512
Giúp mình nha thks
a. 1 + 1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128 + 1/256
b. 3/1x4 + 3/2x5 + 3/3x6 + 3/4x7 + 1/5x8
c. 2/1x3 + 2/3x5 + 2/5x7 + ............... + 2/2001x2003 + 2/2003x2005
Các bn vui lòng giải lời giải nha
Tinh nhanh
5/11+1/2+2/5+6/11+3/4+16/25+5/16
1313/2121+165/165/424242/151515
1/2+1/4+1/8+1/16+1/32+1/64+1/128+1/256
tính nhanh
3/2+4/6+9/8+17/16+33/32+65/64-6=?
giài gùm mình nha
ai nhanh nhất và đúng mình sẽ tick người đó
tính nhanh: 32*9+64*4-64*2+3*32