1. tinh nhanh: 1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128
2. tim x: ( x + 1/2 ) + ( x +1/4 ) + ( x + 1/8 ) + ( x + 1/16 ) = 1
tìm x , biết :
[ x + 1/2 ] + [ x + 1/4 ] + [ x + 1/8 ] + [ x + 1/16 ] = 23/16
{ x + 1/2 } + { x + 1/4 } + { x + 1/8 } + { x + 1/16 } = 1
( x+ 1/2) + (x+1/4)+(x+1/8)+(x+1/16)=1
(x + 1/4) + (x + 1/8) + (x + 1/16) + (x +1/2 ) = 1
(x+1/2)+(x+1/4)+(x+1/8)+(x+1/16)=1
(X+1/2) + (X+1/4) + (X+1/8) + (X+1/16) =1
(x+1/2)+(x+1/4)+(x+1/8)+(x+1/16)=1
Tính nhanh:
(X+1/2) + (X+1/4) + (X+1/8) + (X+1/16)= 1