Bạn chưa đăng nhập. Vui lòng đăng nhập để hỏi bài

Những câu hỏi liên quan
Nguyễn Đức Trí
Xem chi tiết
Trang Nguyễn
Xem chi tiết
Lê Thị Thục Hiền
24 tháng 8 2021 lúc 6:13

a)\(2\sqrt{\dfrac{16}{3}}-3\sqrt{\dfrac{1}{27}}-6\sqrt{\dfrac{4}{75}}\)

\(=2.\sqrt{\dfrac{4^2}{3}}-3.\sqrt{\dfrac{1}{3.3^2}}-6\sqrt{\dfrac{2^2}{3.5^2}}\)

\(=2.\dfrac{4}{\sqrt{3}}-3.\dfrac{1}{3\sqrt{3}}-6.\dfrac{2}{5\sqrt{3}}=\dfrac{8}{\sqrt{3}}-\dfrac{1}{\sqrt{3}}-\dfrac{12}{5\sqrt{3}}\)\(=\dfrac{23}{5\sqrt{3}}=\dfrac{23\sqrt{3}}{15}\)

b)\(\left(6\sqrt{\dfrac{8}{9}}-5\sqrt{\dfrac{32}{25}}+14\sqrt{\dfrac{18}{49}}\right).\sqrt{\dfrac{1}{2}}\)

\(=6\sqrt{\dfrac{8}{9}.\dfrac{1}{2}}-5\sqrt{\dfrac{32}{25}.\dfrac{1}{2}}+14\sqrt{\dfrac{18}{49}.\dfrac{1}{2}}\)

\(=6\sqrt{\dfrac{4}{9}}-5\sqrt{\dfrac{16}{25}}+14\sqrt{\dfrac{9}{49}}\)\(=6.\dfrac{2}{3}-5.\dfrac{4}{5}+14.\dfrac{3}{7}=6\)

c)\(\sqrt{\left(\sqrt{2}-2\right)^2}-\sqrt{6+4\sqrt{2}}=\left|\sqrt{2}-2\right|-\sqrt{4+2.2\sqrt{2}+2}=2-\sqrt{2}-\sqrt{\left(2+\sqrt{2}\right)^2}\)

\(=2-\sqrt{2}-\left(2+\sqrt{2}\right)=-2\sqrt{2}\)

Vân Nguyễn Thị
Xem chi tiết
linh phạm
15 tháng 12 2021 lúc 21:48

\(a.=\dfrac{1}{2}-\dfrac{1}{3}-\dfrac{5}{3}+\dfrac{3}{2}+\dfrac{7}{3}-\dfrac{5}{2}=\dfrac{1+3-5}{2}-\dfrac{2+5-7}{3}=\dfrac{-1}{2}\)

\(b.\left(\dfrac{3}{4}-1\dfrac{1}{6}\right)^2:\sqrt{\dfrac{25}{144}}=\left(-\dfrac{5}{12}\right)^2:\dfrac{5}{12}=\dfrac{5}{12}\)

Sách Giáo Khoa
Xem chi tiết
Thien Tu Borum
19 tháng 4 2017 lúc 18:08

Thực hiện các phép tính:

a) 9,6.212−(2.125−1512):149,6.212−(2.125−1512):14

b) 518−1,456:725+4,5.45518−1,456:725+4,5.45;

c) (12+0,8−113).(2,3+4725−1,28)(12+0,8−113).(2,3+4725−1,28)

d) (−5).12:[(−14)+12:(−2)]+113(−5).12:[(−14)+12:(−2)]+113.

Hướng dẫn làm bài:

a) 9,6.212−(2.125−1512):149,6.212−(2.125−1512):14

=9,6.52−(250−1712)×4=9,6.52−(250−1712)×4

=4,8.5−(1000−173)=4,8.5−(1000−173)

=24−1000+173=24−1000+173

=−976+173=−976+173

=−97013=−97013

b) 518−1,456:725+4,5.45518−1,456:725+4,5.45;

=518−1,456×257+92.45=518−1,456×257+92.45

=518−0,208×25+185=518−0,208×25+185

=518−5,2+185=518−5,2+185

=25−468+32490=25−468+32490

=−11990=−11990

c) (12+0,8−113).(2,3+4725−1,28)(12+0,8−113).(2,3+4725−1,28)

=(12+45−43).(2310+10725−3225)=(12+45−43).(2310+10725−3225)

=(15+24−4030).(2310+10725−3225)=(15+24−4030).(2310+10725−3225)

=(15+24−4030).(115+214−6450)=(15+24−4030).(115+214−6450)

=−130.26550=−130.26550

=−53300=−53300

d) (−5).12:[(−14)+12:(−2)]+113(−5).12:[(−14)+12:(−2)]+113

=−60:[14+12×(−12)]+1.13=−60:[14+12×(−12)]+1.13

=−60:[−14−14]+113=−60:[−14−14]+113

=−60:(12)+113=−60:(12)+113

=120+113=120+113

=12113

Lưu Hạ Vy
19 tháng 4 2017 lúc 18:21

a) \(9,6.2\dfrac{1}{2}-\left(2.125-1\dfrac{5}{12}\right):\dfrac{1}{4}\)

\(=9,6.\dfrac{5}{2}-\left(250-\dfrac{17}{12}\right).4\)

\(=4,8.5-\left(1000-\dfrac{17}{3}\right)\)

\(=24-1000+\dfrac{17}{3}\)

\(=-976+\dfrac{17}{3}=-970\dfrac{1}{3}\)

b) \(\dfrac{5}{18}-1,456:\dfrac{7}{25}+4,5.\dfrac{4}{5}\)

\(=\dfrac{5}{18}-1,456.\dfrac{25}{7}+\dfrac{9}{2}.\dfrac{4}{5}\)

\(=\dfrac{5}{18}-0,208.25+\dfrac{18}{5}\)

\(=\dfrac{5}{18}-5,2+\dfrac{18}{5}\)

\(=-\dfrac{119}{90}\)

c) \(\left(\dfrac{1}{2}+0,8-1\dfrac{1}{3}\right).\left(2,3+4\dfrac{7}{25}-1,28\right)\)

\(=\left(\dfrac{1}{2}+\dfrac{4}{5}-\dfrac{4}{3}\right).\left(\dfrac{23}{10}+\dfrac{107}{25}-\dfrac{32}{25}\right)\)

\(=-\dfrac{1}{30}.\dfrac{265}{50}=-\dfrac{53}{300}\)

d) \(\left(-5\right).12:\left[\left(-\dfrac{1}{4}\right)+\dfrac{1}{2}:\left(-2\right)\right]+1\dfrac{1}{3}\)

\(=-60:\left[\dfrac{1}{4}+\dfrac{1}{2}.\dfrac{-1}{2}\right]+1.\dfrac{1}{3}\)

\(=-60:\left[-\dfrac{1}{4}-\dfrac{1}{4}\right]+1\dfrac{1}{3}\)

\(=-60:\left(\dfrac{1}{2}\right)+1\dfrac{1}{3}\)

\(=121\dfrac{1}{3}\)

Nguyễn Thị Thảo
19 tháng 4 2017 lúc 19:27

a) 9,6.212−(2.125−1512):149,6.212−(2.125−1512):14

=9,6.52−(250−1712)×4=9,6.52−(250−1712)×4

=4,8.5−(1000−173)=4,8.5−(1000−173)

=24−1000+173=24−1000+173

=−976+173=−976+173

=−97013=−97013

b) 518−1,456:725+4,5.45518−1,456:725+4,5.45;

=518−1,456×257+92.45=518−1,456×257+92.45

=518−0,208×25+185=518−0,208×25+185

=518−5,2+185=518−5,2+185

=25−468+32490=25−468+32490

=−11990=−11990

c) (12+0,8−113).(2,3+4725−1,28)(12+0,8−113).(2,3+4725−1,28)

=(12+45−43).(2310+10725−3225)=(12+45−43).(2310+10725−3225)

=(15+24−4030).(2310+10725−3225)

=(15+24−4030).(115+214−6450)=(15+24−4030).(115+214−6450)

=−130.26550=−130.26550

=−53300=−53300

d) (−5).12:[(−14)+12:(−2)]+113

=−60:[14+12×(−12)]+1.13=−60:[14+12×(−12)]+1.13

=−60:[−14−14]+113=−60:[−14−14]+113

=−60:(12)+113=−60:(12)+113

=120+113=120+113

=12113



Trần Thị Thảo
Xem chi tiết
Nguyễn Lê Phước Thịnh
27 tháng 6 2023 lúc 14:09

a: =11+3/4-6-5/6+4+1/2+1+2/3

=10+9/12-10/12+6/12+8/12

=10+13/12=133/12

b: \(=2+\dfrac{17}{20}-1-\dfrac{11}{15}+2+\dfrac{3}{20}\)

=3-11/15

=34/15

c: \(=\dfrac{31}{7}:\left(\dfrac{7}{5}\cdot\dfrac{31}{7}\right)\)

\(=\dfrac{31}{7}:\dfrac{31}{5}=\dfrac{5}{7}\)

d: \(=\dfrac{29}{8}\cdot\dfrac{36}{29}\cdot\dfrac{15}{23}\cdot\dfrac{23}{5}=\dfrac{9}{2}\cdot3=\dfrac{27}{2}\)

Hang Nguyen
Xem chi tiết
Nguyễn Lê Phước Thịnh
22 tháng 7 2021 lúc 20:53

a) Ta có: \(\dfrac{5}{8}+\dfrac{3}{17}+\dfrac{4}{18}+\dfrac{20}{-17}+\dfrac{-2}{9}+\dfrac{21}{56}\)

\(=\left(\dfrac{3}{17}-\dfrac{20}{17}\right)+\left(\dfrac{2}{9}-\dfrac{2}{9}\right)+\left(\dfrac{5}{8}+\dfrac{3}{8}\right)\)

\(=-1+1=0\)

b) Ta có: \(\left(\dfrac{9}{16}+\dfrac{8}{-27}\right)+\left(1+\dfrac{7}{16}+\dfrac{-19}{27}\right)\)

\(=\left(\dfrac{9}{16}+\dfrac{7}{16}\right)+\left(\dfrac{-8}{27}-\dfrac{19}{27}\right)+1\)

=1-1+1=1

 

Vân Nguyễn Thị
Xem chi tiết
Lê Ngọc Anh
Xem chi tiết
Bich Nga Lê
11 tháng 3 2022 lúc 20:02

1) âm năm phần 12

2) âm mười bảy phần 9

3) -1 

Đây là đáp án còn làm bài từ làm nhé

Ngọc Anh
Xem chi tiết
2611
28 tháng 5 2022 lúc 17:28

`1//([-1]/2)^2 . |+8|-(-1/2)^3:|-1/16|=1/4 .8+1/8 .16=2+2=4`

`2//|-0,25|-(-3/2)^2:1/4+3/4 .2017^0=0,25-2,25.4+0,75.1=0,25-9+0,75=-8,75+0,75-8`

`3//|2/3-5/6|.(3,6:2 2/5)^3=|-1/6|.(3/2)^3=1/6 . 27/8=9/16`

`4//|(-0,5)^2+7/2|.10-(29/30-7/15):(-2017/2018)^0=|1/4+7/2|.10-1/2:1=|15/4|.10-1/2=15/4 .10-1/2=75/2-1/2=37`

`5// 8/3+(3-1/2)^2-|[-7]/3|=8/3+(5/2)^2-7/3=8/3+25/4-7/3=107/12-7/3=79/12`