64 x X + X + 32 x X + X x 3 = 805

(64+1+32+3) x X = 805

100 x X = 805

X = 805: 100

X = 8,05

2008 x 68 + 32 x 2008

= 2008 x (68 +32)

= 2008x100= 200800

64 x X + X + 32 x X + X x 3 = 805

X x ( 64 + 1 + 32 + 3 ) = 805

X x ( 65 + 35 ) = 805

X x 100 = 805

X = 805 : 100

X = 8,05

2008 x 68 + 32 x 2008

= 2008 x ( 68 + 32 )

= 2008 x 100

= 200800

1/2+1/4+1/8+1/16+1/32+1/64

=(1/2+1/4+1/8)+(1/16+1/32+1/64)

=(4/8+2/8+1/8)+(4/64+2/64+1/64)

=7/8+7/64

=56/64+7/64

=63/64

           B =        \(\dfrac{1}{2}\) + \(\dfrac{1}{4}\) + \(\dfrac{1}{8}\) +  \(\dfrac{1}{16}\)  + \(\dfrac{1}{32}\) + \(\dfrac{1}{64}\) 

    2 x B   = 1 + \(\dfrac{1}{2}\)+ \(\dfrac{1}{4}\)  +  \(\dfrac{1}{8}\) +  \(\dfrac{1}{16}\)+ \(\dfrac{1}{32}\)

2 x B - B = 1 - \(\dfrac{1}{64}\)

           B = \(\dfrac{63}{64}\)

đặt `A= 1/2 + 1/4 + 1/8 + 1/16+ 1/32 + 1/64`

`=> 2A = 2(1/2 + 1/4 + 1/8 + 1/16+ 1/32 + 1/64)`

`2A = 1+1/2 +1/4 +1/8+1/16 +1/32`

`=>A =2A -A =1+1/2 +1/4 +1/8+1/16 +1/32-1/2-1/4-1/8-1/16-1/32 -1/64`

`A = 1-1/64 = 64/64 -1/64 =63/64`

876 x 64 – 876 x 54 = 876 x ( 64 – 54) = 876 x 10 = 8760

876 x 64 – 876 x 54

= 876 x ( 64 – 54 )

= 876 x 10

= 8760

= 8760

876 x 64 – 876 x 54

= 876 x ( 64 – 54 )

= 876 x 10

= 8760

8760

\(=876\times\left(64-54\right)=876\times10=8760\)

\(\text{8760}\)

voi lai phan so sau hon phan so truoc la 2 doi vi anh nhat linh a?

63/64 do ban oi oi!

qua don giai lop bon da hoc roi goi y cho 

buoc 1 : Dat A

buoc 2:nhan ca hai ve voi N

buoc 3: tru ca hai ve cho nhau

Đặt A = 1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128 + 1/256

=> 2A = 1 + 1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128

=> 2A - A = (1 + 1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128) -                                     (1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128 + 1/256)

=> A = 1 - 1/256

=> A = 255/256

Vậy: ...