a) \(\dfrac{7}{5}.\dfrac{8}{19}+\dfrac{7}{5}.\dfrac{12}{19}-\dfrac{7}{5}.\dfrac{1}{19}\)

\(=\dfrac{7}{5}.\left(\dfrac{8}{19}+\dfrac{12}{19}-\dfrac{1}{19}\right)\)

\(=\dfrac{7}{5}.1\)

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

b) \(\dfrac{-3}{5}.\dfrac{5}{7}+\dfrac{-3}{5}.\dfrac{3}{7}+\dfrac{-3}{5}.\dfrac{6}{7}\)

\(=\dfrac{-3}{5}.\left(\dfrac{5}{7}+\dfrac{3}{7}+\dfrac{6}{7}\right)\)

\(=\dfrac{-3}{5}.2\)

\(=\dfrac{-6}{5}\)

c) \(10\dfrac{2}{9}+\left(2\dfrac{2}{5}-7\dfrac{2}{9}\right)\)

\(=\dfrac{92}{9}+\dfrac{12}{5}-\dfrac{65}{9}\)

\(=\dfrac{92}{9}-\dfrac{65}{9}+\dfrac{12}{5}\)

\(=3+\dfrac{12}{5}\)

\(=\dfrac{15}{5}+\dfrac{12}{5}\)

\(=\dfrac{27}{5}\)

d) \(6\dfrac{3}{10}-\left(3\dfrac{4}{7}+2\dfrac{3}{10}\right)\)

\(=\dfrac{63}{10}-\dfrac{25}{7}-\dfrac{23}{10}\)

\(=\dfrac{63}{10}-\dfrac{23}{10}-\dfrac{25}{7}\)

\(=4-\dfrac{25}{7}\)

\(=\dfrac{28}{7}-\dfrac{25}{7}\)

\(=\dfrac{3}{7}\)

Chúc bạn học tốt

`@` `\text {Ans}`

`\downarrow`

`a)`

\(\dfrac{7}{5}\cdot\dfrac{8}{19}+\dfrac{7}{5}\cdot\dfrac{12}{19}-\dfrac{7}{5}\cdot\dfrac{1}{19}\)

`=`\(\dfrac{7}{5}\cdot\left(\dfrac{8}{19}+\dfrac{12}{19}-\dfrac{1}{19}\right)\)

`=`\(\dfrac{7}{5}\cdot\dfrac{19}{19}=\dfrac{7}{5}\cdot1=\dfrac{7}{5}\)

`b)`

\(-\dfrac{3}{5}\cdot\dfrac{5}{7}+\left(-\dfrac{3}{5}\right)\cdot\dfrac{3}{7}+\left(-\dfrac{3}{5}\right)\cdot\dfrac{6}{7}\)

`=`\(-\dfrac{3}{5}\cdot\left(\dfrac{5}{7}+\dfrac{3}{7}+\dfrac{6}{7}\right)\)

`=`\(-\dfrac{3}{5}\cdot\dfrac{14}{7}\)

`=`\(-\dfrac{3}{5}\cdot2=-\dfrac{6}{5}\)

`c)`

\(10\dfrac{2}{9}+\left(2\dfrac{2}{5}-7\dfrac{2}{9}\right)\)

`=`\(10\dfrac{2}{9}+2\dfrac{2}{5}-7\dfrac{2}{9}\)

`=`\(\left(10\dfrac{2}{9}-7\dfrac{2}{9}\right)+2\dfrac{2}{5}\)

`=`\(3+2\dfrac{2}{5}=\dfrac{27}{5}\)

`d)`

\(6\dfrac{3}{10}-\left(3\dfrac{4}{7}+2\dfrac{3}{10}\right)\)

`=`\(6\dfrac{3}{10}-3\dfrac{4}{7}-2\dfrac{3}{10}\)

`=`\(\left(6\dfrac{3}{10}-2\dfrac{3}{10}\right)-3\dfrac{4}{7}\)

`=`\(4-3\dfrac{4}{7}=\dfrac{3}{7}\)

làm ơn giúp mình ,bạn nào làm nhanh đúng mình chọn cho nhanh nha mọi người

nhanh nha mọi người

T.T

Bài làm

2².4⁴.2⁶.2.2=2².2⁸.2⁶.2²=2¹⁸

2.2³.2⁷.2⁴=2¹⁵

3².3=3³=27

3⁴.3³.3=3⁸

3.3⁵.3⁴.3²=3¹²

3.3⁶.3⁷.3⁴=3¹⁸

4.4³=4⁴

4⁵.4.4⁷=4¹³

4.4³.4⁵.4⁶=4¹⁵

5.5⁶=5⁷

5.5⁴=5⁵

5.5².5⁴=5⁷

5.5³.5⁴.5⁶=5¹⁴

5.5⁶.5⁴.5³=5¹⁴

x.x²=x³

x.x³.x⁵=x⁹

a.a⁴=a⁵

a.a².a⁴.a⁵.a⁷=a¹⁹

a.a³.a⁵.a⁶=a¹⁵

a.a⁴.a.a⁵.a⁶.a=a¹⁸

x.x³.x⁴=x⁸

x⁵.x⁴.x.x⁷.x⁶=x²³

7.7²=7³

7.7².7⁴.7⁵=7¹²

7³.7⁵.7⁴.7=7¹³

7².7.7⁶.7⁶.7³=7¹⁸

10.10²=10³

10.100.10³=10⁶

10.100.10⁴.1000=10¹⁰

10².10⁴.100.1000=10¹¹

Tk nha !

a: \(=5^2+2^5-1=25+32-1=25+31=56\)

c: \(=\dfrac{-7}{25}\cdot\dfrac{39}{14}\cdot\dfrac{50}{78}\)

\(=\dfrac{-7}{14}\cdot\dfrac{39}{78}\cdot\dfrac{50}{25}=\dfrac{-1}{2}\)

d: \(=\left(\dfrac{3}{8}-\dfrac{3}{4}+\dfrac{7}{12}\right)\cdot\dfrac{6}{5}+\dfrac{1}{2}\)

\(=\dfrac{9-18+14}{24}\cdot\dfrac{6}{5}+\dfrac{1}{2}\)

\(=\dfrac{1}{4}+\dfrac{1}{2}=\dfrac{3}{4}\)

a: \(=\dfrac{-3}{5}\cdot\dfrac{5}{7}+\dfrac{-3}{5}\cdot\dfrac{3}{7}+\dfrac{-3}{5}\cdot\dfrac{6}{7}\)

\(=\dfrac{-3}{5}\left(\dfrac{5}{7}+\dfrac{3}{7}+\dfrac{6}{7}\right)=\dfrac{-3}{5}\cdot2=-\dfrac{6}{5}\)

b: \(=\dfrac{3}{13}\cdot\dfrac{6}{11}+\dfrac{3}{13}\cdot\dfrac{5}{11}-\dfrac{2}{13}=\dfrac{3}{13}-\dfrac{2}{13}=\dfrac{1}{13}\)

c: =>1/2x+1+3/8=7/16

=>1/2x=-15/16

=>x=-15/8

d: =>5/2x-1/3=1/6*(-9)/2=-9/12=-3/4

=>5/2x=-3/4+1/3=-9/12+4/12=-5/12

=>x=-1/6

giải giùm e vs ạ

                                                                         Bài làm

1.

11 3/13 - ( 2 4/7 + 5 3/13 )

= 11 3/13 - 2 4/7 - 5 3/13

= ( 11 3/13 - 5 3/13 ) - 2 4/7

= { (11 - 5 ) . ( 3/13 - 3/13 ) } - 2 4/7

= ( 6 . 0 ) - 2 4/7

= 0 - 2 4/7

= 2 4/7

= 18/7

2 .

19 5/8 : 7/12 + ( -15 1/4) : 7/12

= { 19 5/8 + ( -15 1/4 ) } : 7/12

= [ { 19 + ( - 15) } . ( 5/8 + 1/4 ) ] : 7/12

= { 4 . ( 5/8 + 2/8 ) } : 7/12

= ( 4 . 7/8 ) : 7/12

= 1.7/2 : 7/12

= 7/2 : 7/12

= 7/2 . 12/7

= 1.1/6.1

= 1/6

3 .

2/5 . 1/3 - 2 2/15 : 1/5 + 3/5 . 1/3

= 1/3 . ( 2/5 + 3/5 ) - 2 2/15 : 1/5

= 1/3 . 5/5 - 32/15 . 5/1

= 1/3 . 1 - 32.1/3.1

= 1/3 - 32/3

= -31/3

4 .

( 3 1/3 + 2,5 ) : ( 3 1/6 - 4 1/5 ) - 11/31

= ( 10/3 + 25/10 ) : { ( 3 - 4 ) . ( 1/6 - 1/5 ) - 11/31

= ( 10/3 + 5/2 ) : { (-1) . ( 5/30 - 6/30 ) } - 11/31

= ( 20/6 + 15/6 ) : { (-1) . (-1)/30 } - 11/31

= 35/6 : 1/30 - 11/31

= 35/6 . 30/1 - 11/31

= 35.5/1.1 - 11/31

= 175 - 11/31

= 5425/31 - 11/31

= 5414/31

5.

75% - 1 1/5 + 0,5 : 5/12 - (-1/2)²

= 75/100 - 6/5 + 5/12 - 1/4

= 3/4 - 6/5 + 5/12 - 1/4

= ( 3/4 - 1/4 ) + ( 5/12 - 6/5 )

= 2/4 + ( 25/60 - 30/60 )

= 1/2 + (-5)/60

= 1/2 + (-1)/12

= 6/12 + (-1)/12

= 5/12

Đúng thì k cho mình nha !

1)

11 3/13 - ( 2 4/7 + 5 3/13 )

= 11 3/13 - 2 4/7 - 5 3/13

= ( 11 3/13 - 5 3/13 ) - 2 4/7

= { (11 - 5 ) . ( 3/13 - 3/13 ) } - 2 4/7

= ( 6 . 0 ) - 2 4/7

= 0 - 2 4/7

= 2 4/7

= 18/7

2 )

19 5/8 : 7/12 + ( -15 1/4) : 7/12

= { 19 5/8 + ( -15 1/4 ) } : 7/12

= [ { 19 + ( - 15) } . ( 5/8 + 1/4 ) ] : 7/12

= { 4 . ( 5/8 + 2/8 ) } : 7/12

= ( 4 . 7/8 ) : 7/12

= 1.7/2 : 7/12

= 7/2 : 7/12

= 7/2 . 12/7

= 1.1/6.1

= 1/6

3 )

2/5 . 1/3 - 2 2/15 : 1/5 + 3/5 . 1/3

= 1/3 . ( 2/5 + 3/5 ) - 2 2/15 : 1/5

= 1/3 . 5/5 - 32/15 . 5/1

= 1/3 . 1 - 32.1/3.1

= 1/3 - 32/3

= -31/3

4 )

( 3 1/3 + 2,5 ) : ( 3 1/6 - 4 1/5 ) - 11/31

= ( 10/3 + 25/10 ) : { ( 3 - 4 ) . ( 1/6 - 1/5 ) - 11/31

= ( 10/3 + 5/2 ) : { (-1) . ( 5/30 - 6/30 ) } - 11/31

= ( 20/6 + 15/6 ) : { (-1) . (-1)/30 } - 11/31

= 35/6 : 1/30 - 11/31

= 35/6 . 30/1 - 11/31

= 35.5/1.1 - 11/31

= 175 - 11/31

= 5425/31 - 11/31

= 5414/31

5)

75% - 1 1/5 + 0,5 : 5/12 - (-1/2)²

= 75/100 - 6/5 + 5/12 - 1/4

= 3/4 - 6/5 + 5/12 - 1/4

= ( 3/4 - 1/4 ) + ( 5/12 - 6/5 )

= 2/4 + ( 25/60 - 30/60 )

= 1/2 + (-5)/60

= 1/2 + (-1)/12

= 6/12 + (-1)/12

= 5/12

1=18/7

2=1/6

3=31/3

4=5414/31

5=5/12