Tính bằng cách thuận tiện nhất chỉ cần đáp án thôi nhé.
1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128 + 1/256
tính bằng cách thuận tiện nhất:
1/2+1/4+1/8+1/16+1/32+1/64+1/128+1/256
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: ...
tính thuận tiện
1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128 + 1/256+ 1/ 512
ai nhanh mình tick
1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128 + 1/256 + 1/512
= 1/2 - 1/4 + 1/4 - 1/8 + 1/8 - 1/16 + ... + 1/256 - 1/512
= 1/2 - 1/512
= 255/512
Gọi \(\frac{1}{4}+\frac{1}{8}+\frac{1}{6}+\frac{1}{32}+\frac{1}{64}+\frac{1}{128}+\frac{1}{256}+\frac{1}{512}\) là A
Ta có :
\(A=\frac{1}{4}+\frac{1}{8}+\frac{1}{16}+\frac{1}{32}+\frac{1}{64}+\frac{1}{128}+\frac{1}{256}+\frac{1}{512}\)
\(2A=2.\left(\frac{1}{4}+\frac{1}{8}+\frac{1}{16}+\frac{1}{32}+\frac{1}{64}+\frac{1}{128}+\frac{1}{256}+\frac{1}{512}\right)\)
\(2A=\frac{1}{2}+\frac{1}{4}+\frac{1}{8}+\frac{1}{16}+\frac{1}{32}+\frac{1}{64}+\frac{1}{128}+\frac{1}{256}\)
\(2A-A=\left(\frac{1}{2}+\frac{1}{4}+\frac{1}{8}+\frac{1}{16}+\frac{1}{32}+\frac{1}{64}+\frac{1}{128}+\frac{1}{256}\right)-\left(\frac{1}{4}+\frac{1}{8}+\frac{1}{16}+\frac{1}{32}+\frac{11}{64}+\frac{1}{128}+\frac{1}{256}+\frac{1}{512}\right)\)
\(A=\frac{1}{2}-\frac{1}{512}\)
\(A=\frac{255}{512}\)
Vậy ..........
tính bằng cách thuận tiện nhất B 1/2+1/4+1/8+1/16+1/32+1/64
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 = \(\dfrac{63}{64}\)
tính bằng cách thuận tiện nhất
A=1/2 + 1/4 + 1/8 + 1/16+ 1/32 + 1/64
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`
tính bằng cách thuận tiện nhất
1\2+1\4+1\8+1\16+1\32+1\64
voi lai phan so sau hon phan so truoc la 2 doi vi anh nhat linh a?
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
tính tổng dưới đây bằng cách nhanh nhất:
1/2+1/4+1/8+1/16+1/32+1/64+1/128+1/256+1/512+1/1204
bằng 511/512
Cho 1/2+1/4+1/8+1/16+1/32+1/64+1/128+1/256
Các bạn hãy cho mình cách giải nhanh nhất và chỉ tiết nhé!Ai làm nhanh và đúng mình tk cho!!!!??
= 128/256 + 64/256 + 32/256 + 16/256 + 8/256 + 4/256 + 2/256 + 1/256
= 255/256
quy đồng mẫu số bạn nhé. Mẫu số chung = 256
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tính tổng các phân số sau bằng cách thuận tiện nhất:
1/2, 1/4, 1/8, 1/16, 1/32, 1/64
Tính bằng cách thuận tiện nhất: 49/5-1/2-1/4-1/8-1/16-1/32=