Hicc mình hông còn tgian mấy bạn giúp minh 2 câu thui cũng đc ạk

a)  5/9 + 4/9 . 3/7 + 4/9 . 4/7

  = 5/9 + 4/9 . (3/7 + 4/7)

  = 5/9 + 4/9 . 1

  = 5/9 + 4/9

  = 1 

mình lười nghĩ lắm sorry

a)

15 . ( - 2 ) . ( - 5 ) . ( - 6 )

= [( 15 . ( - 2 )] . [( - 5 ) . ( - 6 )]

= - 30 . 30

= - 900

b)

4 . 7 . ( - 11 ) . ( - 2 )

= ( 4 . 7 ) . [( - 11 ) . ( - 2 )]

= 28 . 22

= 616 

a)15. (-2).(-5).(-6)

=(-30).(-5).(-6)

=150.(-6)

=-900

b)4.7.(-11).(-2)

=28.(-11).(-2)

=(-308).(-2)

=616

a , 15 . ( - 2 ) . ( - 5 ) . ( - 6 ) = ( - 30 ) . 30 = -90

b , 4 . 7 . ( - 11 ) . ( - 2 ) = 28 . 22 = 616

a) 15 . (-2) . (-5) . (-6)           b.  4 . 7 . (-11) . (-2) 

= [15 . (-6)] . [(-2) . (-5)]            = [4 . 7 . (-2)] . (-11)

= (-90) . 10 = -900.                    = (28. (-2)) . (-11) = (-56) . (-11) = 616.

a, 

15.(-2).(-5).(-6)

=  (-30).(-5).(-6)

=  150 . (-6)

= -900

b,    

4.7.(-11).(-2)

= 28 .(-11).(-2)

= (-308) . (-2)

= 616

Thực hiện các phép tính :

a) 15.(-2).(-5).(-6)

= 15. (-6). (-2). (-5)

= -90. 10

= -900

b)4.7.(-11).(-2)

= 28. 22

= 616

\(a) 15.(-2).(-5).(-6) \)

\(= [15.(-2)].(-5).(-6)\)

\(= [(- 30) . (-5)].(-6)\)

\(= 150 . (-6)\)

\(= -900\)

\(b)4.7.(-11).(-2)\)

\(= (4.7).(-11).(-2) \)

\(= 28.(-11).(-2)\)

\(= -308.(-2)\)

\(= 616\)

a) -5/7.7/10 - 3/11 : 6/5

= -1/2 - 5/22

= -8/11

b) 5/14.1/3.-4/15:5/7

= -2/63:5/7 = -2/45

c) 2 13/15.11/15 - 13/15 + 2 13/15.4/15

= 2 13/15.(11/15 + 4/15) - 13/15

= 2 13/15.1 - 13/15

= 2 13/15 - 13/15

= 2

1) 5 + (-4) = 1

2) (-8) + 2 = -6

3) 8 + (-2) = 6

4) 11 + (-3) = 8

5) (-11) + 2 = -9

6) (-7) + 3 = -4

7) (-5) + 5 = 0

8) 11 + (-12) = -1

9) (-18) + 20 = 2

10) (15) + (-12) = 3

11) (-17) + 17 = 0

12) 16 + (-2) = 14

13) (30) + (-14) = 16

14) (-19) + 20 = 1

15) (-18) + 15 = -3

16) (10) + (-6) = 4

17) (-28) + 14 = -14

18) 15 + (-30) = -15

19) (15) + (-4) = 11

20) (-21) + 11 = -10

21) 8 + (-22) = -14

22) (-15) + 4 = -11

23) (-3) + 2 = -1

24) 17 + (-14) = 3

25) 17 + (-14) = 3

thế này đọc đc mới đỉnh

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

a,     (\(\dfrac{9}{10}\) - \(\dfrac{15}{16}\)) \(\times\) ( \(\dfrac{5}{12}\) - \(\dfrac{11}{15}\) - \(\dfrac{7}{20}\))

=  (\(\dfrac{72}{80}\) - \(\dfrac{75}{80}\))  \(\times\) (\(\)\(\dfrac{25}{60}\) - \(\dfrac{44}{60}\)  - \(\dfrac{21}{60}\))

= - \(\dfrac{3}{80}\)  \(\times\) (- \(\dfrac{2}{3}\))

= \(\dfrac{1}{40}\) 

b, (-1)³ + (- \(\dfrac{2}{3}\))² : 2\(\dfrac{2}{3}\) + \(\dfrac{5}{6}\)

=  -1³ +   \(\dfrac{4}{9}\) : \(\dfrac{8}{3}\) + \(\dfrac{5}{6}\)

= -1 + \(\dfrac{4}{9}\) \(\times\) \(\dfrac{3}{8}\) + \(\dfrac{5}{6}\)

= -1 + \(\dfrac{1}{6}\) + \(\dfrac{5}{6}\)
= -1 + 1

= 0

c, 15 \(\times\) (- \(\dfrac{1}{5}\))² + \(\dfrac{1}{5}\) - 2 \(\times\) (- \(\dfrac{1}{2}\))³ - \(\dfrac{1}{2}\)

= 15 \(\times\) \(\dfrac{1}{25}\) + \(\dfrac{1}{5}\) - 2 \(\times\) (- \(\dfrac{1}{8}\)) - \(\dfrac{1}{2}\)

=  \(\dfrac{3}{5}\)  + \(\dfrac{1}{5}\) + \(\dfrac{1}{4}\) - \(\dfrac{1}{2}\)

= \(\dfrac{4}{5}\) - \(\dfrac{1}{4}\)

= \(\dfrac{11}{20}\)