1+2+4+5+7+4+10+54+147+521+1044+...+1427+1200=?
tính
1.\(\sqrt{147}+\sqrt{54}-4\sqrt{27}\)
2.\(\sqrt{28}-4\sqrt{63}+7\sqrt{112}\)
3.\(\sqrt{49}-5\sqrt{28}+\dfrac{1}{2}\sqrt{63}\)
4.\(\left(2\sqrt{6}-4\sqrt{3}-\dfrac{1}{4}\sqrt{8}\right).3\sqrt{6}\)
5.(\(2\sqrt{1\dfrac{9}{16}}-5\sqrt{5\dfrac{1}{16}}\)):\(\sqrt{16}\)
6.\(\left(\sqrt{48}-3\sqrt{27}-\sqrt{147}\right):\sqrt{3}\)
7.\(\left(\sqrt{50}-3\sqrt{49}\right):\sqrt{2}-\sqrt{162}:\sqrt{2}\)
8.\(\left(2\sqrt{1\dfrac{9}{10}}-\sqrt{5\dfrac{1}{10}}\right):\sqrt{10}\)
9.\(2\sqrt{\dfrac{16}{3}}-3\sqrt{\dfrac{1}{27}}-6\sqrt{\dfrac{4}{75}}\)
10.\(2\sqrt{27}-6\sqrt{\dfrac{4}{3}}+\dfrac{3}{5}\sqrt{75}\)
11.\(\dfrac{\sqrt{18}}{\sqrt{2}}-\dfrac{\sqrt{12}}{\sqrt{3}}\)
12.\(\dfrac{\sqrt{27}}{\sqrt{3}}+\dfrac{\sqrt{98}}{\sqrt{2}}-\sqrt{175}:\sqrt{7}\)
13.\(\left(\dfrac{\sqrt{8}}{\sqrt{2}}-\dfrac{\sqrt{180}}{\sqrt{5}}\right).\sqrt{5}-\sqrt{\dfrac{81}{11}}.\sqrt{11}\)
14.\(\sqrt{8\sqrt{3}}-2\sqrt{25\sqrt{12}}+4\sqrt{\sqrt{192}}\)
15.\(\left(3\sqrt{2}-2\sqrt{3}\right)\left(3\sqrt{2}+2\sqrt{3}\right)\)
16.\(\left(1+\sqrt{5}-\sqrt{3}\right)\left(1+\sqrt{5}+\sqrt{3}\right)\)
D=√147 +√54 -4√27
A =√112 - 7√(1/7) - 14√(1/28)-21/√7
B = 3√2(4 -√2) + 3(1 - 2√2)^2
C = 2√27 + 5√12 - 3√48
E = (√15 - 2√3)^2 + 12√5
F = 3√50 - 7√8 + 12√18
G = 2√80 - 2√245 + 2√180
H =√28 - 4√63 + 7√112
I =√44 -√176 + 2√275
cái này bấm máy tính là thầy mình k cho đâu =))) phải trình bày ra mà
D=√147 +√54 -4√27
A =√112 - 7√(1/7) - 14√(1/28)-21/√7
B = 3√2(4 -√2) + 3(1 - 2√2)^2
C = 2√27 + 5√12 - 3√48
E = (√15 - 2√3)^2 + 12√5
F = 3√50 - 7√8 + 12√18
G = 2√80 - 2√245 + 2√180
H =√28 - 4√63 + 7√112
I =√44 -√176 + 2√275
32.(132-247)-132.(32-247)
135.(-12+147)-147.(135-12)
1-4+7-10+...+2995-2998
1-2-3+4+5-6-7+8+...+2004+2005
Ai giải được tôi sẽ cho tiền$
1) 2310:35 2)598 : 23 3)1596 : 42 4)1044:29 5)4968:72
1) 2310 : 35 = 66
2) 598 : 23 = 26
3) 1596 : 42 = 38
4) 1044 : 29 = 36
5) 4968 : 72 = 69
1.Tính bằng cách thuận tiện nhất:
a.17/2 x 4/7 + 4/7 x 1/2 + 4/7 b.1515/2323 x 69/54 x 2727/1515
2. Một hình bình hành có diện tích 1200 cm2 . Độ dài cạnh đáy 60cm . Chiều cao của hình bình hành là bao nhiêu đề-xi-mét?
a. \(\left(\dfrac{17}{2}+\dfrac{1}{2}+1\right).\dfrac{4}{7}\)
\(=\dfrac{19}{2}.\dfrac{4}{7}=\dfrac{38}{7}\)
b. \(\dfrac{2727}{2323}.\dfrac{69}{54}\)
\(=\dfrac{27}{23}.\dfrac{23.3}{27.2}=\dfrac{3}{2}\)
2. Chiều cao hình bình hành là: 1200 : 60 = 20 cm
a, \(\dfrac{17}{2}\) \(\times\) \(\dfrac{4}{7}\) + \(\dfrac{4}{7}\) \(\times\) \(\dfrac{1}{2}\) + \(\dfrac{4}{7}\) b, \(\dfrac{1515}{2323}\) \(\times\) \(\dfrac{69}{54}\) \(\times\) \(\dfrac{2727}{1515}\)
= \(\dfrac{17}{2}\) \(\times\) \(\dfrac{4}{7}\) + \(\dfrac{4}{7}\) \(\times\) \(\dfrac{1}{2}\) + \(\dfrac{4}{7}\) \(\times\) 1 = \(\dfrac{15}{23}\) \(\times\) \(\dfrac{23}{18}\) \(\times\) \(\dfrac{27}{15}\)
= \(\dfrac{4}{7}\) \(\times\) ( \(\dfrac{17}{2}\) + \(\dfrac{1}{2}\) + 1) = \(\dfrac{27}{18}\)
= \(\dfrac{4}{7}\) \(\times\) ( 9 + 1) = \(\dfrac{3}{2}\)
= \(\dfrac{4}{7}\times10\)
= \(\dfrac{40}{7}\)
Bài 2: Chiều cao của hình bình hành là:
1200 : 60 = 20 cm
Đổi 20 cm = 2 dm
Đáp số: 2 dm
1) x+1/2=-5/3
2) 1/3-x=3/5
4) x-4/3=-7/9
5) x--7/3=5/6
6) x-1/5=9/10
7) x+5/12=3/8
8) x+5/4=7/6
9) x-2/7=1/35
10) x-2/7=-7/10
6: =>x=9/10+1/5=9/10+2/10=11/10
7: =>x=3/8-5/12=36/96-40/96=-1/24
8: =>x=7/6-5/4=14/12-15/12=-1/12
9: =>x=1/35+2/7=1/35+10/35=11/35
10: =>x=2/7-7/10=20/70-49/70=-29/70
1, \(x=-\dfrac{5}{3}-\dfrac{1}{2}=-\dfrac{10}{6}-\dfrac{3}{6}=-\dfrac{13}{6}\)
2, \(x=\dfrac{1}{3}-\dfrac{3}{5}=\dfrac{5-9}{15}=-\dfrac{4}{15}\)
4, \(x=-\dfrac{7}{9}+\dfrac{4}{3}=\dfrac{-7+12}{9}=\dfrac{5}{9}\)
5, \(x=\dfrac{5}{6}-\dfrac{7}{3}=\dfrac{5-14}{6}=-\dfrac{9}{6}=-\dfrac{3}{2}\)
6, \(x=\dfrac{9}{10}+\dfrac{1}{5}=\dfrac{9+2}{10}=\dfrac{11}{10}\)
7, \(x=\dfrac{3}{8}-\dfrac{5}{12}=\dfrac{9-10}{12}=-\dfrac{1}{12}\)
8, \(x=\dfrac{7}{6}-\dfrac{5}{4}=\dfrac{14-15}{12}=-\dfrac{1}{12}\)
9, \(x=\dfrac{1}{35}+\dfrac{2}{7}=\dfrac{1+10}{35}=\dfrac{11}{35}\)
10, \(x=-\dfrac{7}{10}+\dfrac{2}{7}=\dfrac{-49+20}{70}=\dfrac{-29}{70}\)
a ) 10/3 - 8/3
11/4 - 5/4
32/17 + 21/17
b ) 5/6 + 7/8
3/7 - 5/14
7/4 - 3/5
Help
a: 10/3-8/3=2/3
11/4-5/4=6/4=3/2
32/17+21/17=53/17
b: 5/6+7/8=20/24+21/24=41/24
3/7-5/14=6/14-5/14=1/14
7/4-3/5=35/20-12/20=23/20
a: 10/3-8/3=2/3
11/4-5/4=6/4=3/2
32/17+21/17=53/17
b: 5/6+7/8=20/24+21/24=41/24
3/7-5/14=6/14-5/14=1/14
7/4-3/5=35/20-12/20=23/20
a: 10/3-8/3=2/3
11/4-5/4=6/4=3/2
32/17+21/17=53/17
b: 5/6+7/8=20/24+21/24=41/24
3/7-5/14=6/14-5/14=1/14
7/4-3/5=35/20-12/20=23/20
1.so sánh
1/2:2/3......2/3:1/2 4/7:2/5......4/7:3/5
4/15:4/7......2/5x10/3 5/6......15/18-11/18
2.viết số thích hợp vào ô trống
2/3=..../18 7/9=49/.... ..../5=18/15
..../3=10/15 5/9=..../45 49/56=7/....
6/8=42/.... 2/9=..../63 49/56=..../8
`1)1/2:2/3 .... 2/3 : 1/2`
`=>1/2xx3/2 .... 2/3xx2`
`=>3/4 .... 4/3`
Vì `3/4 < 1` và `4/3>1`
`=>3/4<4/3`
__
`4/7:2/5 ... 4/7 : 3/5`
`=>4/7xx5/2....4/7xx5/3`
`=>20/14...20/21`
`=>10/7...20/21`
Vì `10/7>1` và `20/21<1`
`=>10/7>20/21`
__
`4/15:4/7....2/5xx10/3`
`=>4/15xx7/4...20/15`
`=>7/15...20/15`
Vì `7<20` nên `7/15<20/15`
__
`5/6...15/18-11/18`
`=>5/6...4/18`
Ta có : MSC : `18`
`5/6 = 15/18`
Vì `15>4` nên `5/6 > 4/18`
`2)2/3=(2xx6)/(3xx6)=12/18`
`7/9=(7xx7)/(9xx7)=49/63`
`6/5=(6xx3)/(5xx3)=18/15`
`2/3=(2xx5)/(3xx5)=10/15`
`5/9=(5xx5)/(9xx5)=25/45`
`49/56=(49:7)/(56:7)=7/8`
`6/8=(6xx7)/(8xx7)=42/56`
`2/9=(2xx7)/(9xx7)=14/63`
`49/56=(49:7)/(56:7)=7/8`