1/2+1/4+1/8 +.....+1/120+1/124+1/128
Những câu hỏi liên quan
1.Tính nhanh:
a)1+2+3+4+...+2001+2002
b)2+4+6+8+...+100
c)132+128+124+...+76+72+68
GIÚP MÌNH NHA
a, 1+2+3+4+....+2001+2002=(2002+1).[(2002-1)+1] :2
=2003.1001
= 2005003
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4 tháng 6 2021 lúc 19:07
Thực hiện phép tính: (Tính nhanh nếu có thể)1) 347.22 – 22 . ( 216 + 184 ) : 8 ; 2) 132 – [116 – ( 132 – 128 )2] ;3) 16 :{400 : [200 – ( 37 + 46 . 3 )]} ; 4) {184 : [96 – 124 : 31 ] – 2 }. 3651 ; 5) 46 – [ (16 + 71 . 4 ) : 15 ]} – 2 ; 6) 33.18 + 72 .42 – 41 .187)( 56 . 46 – 25 . 23 ) : 23 ; 8) ( 28 . 54 + 56 . 36 ) : 21 : 2 ;9) ( 76 . 34 – 19 . 64 ) : ( 38 . 9 ) ; 10) ( 2+ 4...
Đọc tiếp
Thực hiện phép tính: (Tính nhanh nếu có thể)
1) 347.22 – 22 . ( 216 + 184 ) : 8 ;
2) 132 – [116 – ( 132 – 128 )2] ;
3) 16 :{400 : [200 – ( 37 + 46 . 3 )]} ;
4) {184 : [96 – 124 : 31 ] – 2 }. 3651 ;
5) 46 – [ (16 + 71 . 4 ) : 15 ]} – 2 ;
6) 33.18 + 72 .42 – 41 .18
7)( 56 . 46 – 25 . 23 ) : 23 ;
8) ( 28 . 54 + 56 . 36 ) : 21 : 2 ;
9) ( 76 . 34 – 19 . 64 ) : ( 38 . 9 ) ;
10) ( 2+ 4 + 6 + ….. + 100 ) . ( 36 . 333 – 108 . 111)
11) ( 5 . 411- 3 .165 ): 410
12) \(\dfrac{7256.4375-725}{3650+4375.7255}\)
Thuc hien phep tinh:
a.3/7.11/15+3/7:15/14+2/7
b.(-7/15).5/8.15/-7(-32)
c.[(1/9:8/27):-1/3]:81/128
d.-66(1/2-1/3+1/11)+124(-37)+63(-124)
Bài 1: tìm x
a) (x+9) + (x-2)+(x+7)+ (x-4)+(x+5) +(x-6)+(x-3)+ (x-8)+(x+1)=95
b) { [( x:2) - ½] :4 - ¼} : 5= 5+ 1/5
Bài 2: tìm X
a) 72 : { 16- [ 47 + ( x-2)]} = 9
b) x + 132 + 128 +124 +... + 76 + 68 = 2016
X*[1/2+1/4+1/8+1/16+1/32+1/64+1/128]=127/128
X x (1/2+1/4+1/8+1/16+1/32+1/64+1/128) = 127/128
X x 127/128 = 127/128
X = 127/128 : 127/128
X = 1
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
tính nhanh p/s 1+ 5/4 + 5/8 + 5/16 + 5/32 + 5/64b) 1/3 +1/9 + 1/27 + 1/81 +...........+ 1/59049c) 3/2 + 3/8 + 3/32 +3/128 + 3/512d) 1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128 + 1/256 giúp mình với
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tính nhanh p/s 1+ 5/4 + 5/8 + 5/16 + 5/32 + 5/64
b) 1/3 +1/9 + 1/27 + 1/81 +...........+ 1/59049
c) 3/2 + 3/8 + 3/32 +3/128 + 3/512
d) 1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128 + 1/256 giúp mình với 
b: A=1/3+1/9+...+1/3^10
=>3A=1+1/3+...+1/3^9
=>A*2=1-1/3^10=(3^10-1)/3^10
=>A=(3^10-1)/(2*3^10)
c: C=3/2+3/8+3/32+3/128+3/512
=>4C=6+3/2+...+3/128
=>3C=6-3/512
=>C=1023/512
d: A=1/2+...+1/256
=>2A=1+1/2+...+1/128
=>A=1-1/256=255/256
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1/2+1/4+1/8+1/16+.......+1/124 = ?
1/2+1/4+1/8+...+1/128
`1/2+1/4+1/8+...+1/128`
`=1/2x2+1/4x2+1/8x2+...+1/128x2`
`=1+1/2+1/4+1/8+...+1/64`
`=1+1/2+1/4+1/8+...+1/64-1/2-1/4-1/8-...-1/128`
`=1-1/128`
`=127/128`
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\(\dfrac{1}{2}+\dfrac{1}{4}+\dfrac{1}{8}+...+\dfrac{1}{128}\)
\(=1-\dfrac{1}{128}\)
\(=\dfrac{128}{128}-\dfrac{1}{128}\)
\(=\dfrac{127}{128}\)
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