lam cho minh cai

\(\frac{1}{2}\cdot\left(\frac{2}{9}+\frac{3}{7}-\frac{5}{27}\right)=\frac{1}{2}\cdot\left(\frac{6}{27}-\frac{5}{27}+\frac{3}{7}\right)=\frac{1}{2}\cdot\frac{3}{7}+\frac{1}{2}\cdot\frac{1}{27}=\frac{3}{14}+\frac{1}{54}=\frac{44}{189}\)

\(\frac{1}{2}+\frac{3}{4}-\left(\frac{3}{4}-\frac{4}{5}\right)=\frac{1}{2}+\frac{3}{4}-\frac{3}{4}+\frac{4}{5}=\frac{1}{2}+\frac{4}{5}=\frac{13}{10}\)

\(\frac{1}{3}\cdot\frac{5}{7}-\frac{7}{27}\cdot\frac{36}{14}=\frac{1}{3}\cdot\frac{5}{7}-\frac{7}{27}\cdot\frac{18}{7}=\frac{1}{3}\cdot\frac{5}{7}-\frac{6}{7}=\frac{5}{21}-\frac{14}{21}=\frac{-3}{7}\)

2: 

a: =>x=1/2+1/6=3/6+1/6=4/6=2/3

b: =>x+3,5=7,8-6,3=1,5

=>x=1,5-3,5=-2

c: =>(35-x)/-105=1/5

=>35-x=-21

=>x=56

1

c hình như tính bình thường thôi:v

d

= 1,75 : 5 + 2,5 . (16 – 4 . 4,1)

= 1,75 : 5 + 2,5 . (16 – 16,4)

= 1,75 : 5 + 2,5 . (−0,4)

= 0,35 − 1

= −0,65.

2

a

\(\Rightarrow x=\dfrac{1}{2}+\dfrac{1}{6}=\dfrac{3}{6}+\dfrac{1}{6}=\dfrac{4}{6}=\dfrac{2}{3}\)

b

\(\Rightarrow x+\dfrac{35}{10}=\dfrac{78}{10}-\dfrac{63}{5}:2\\ \Rightarrow x+\dfrac{35}{10}=\dfrac{78}{10}-\dfrac{63}{10}=\dfrac{15}{10}\\ \Rightarrow x=\dfrac{15}{10}-\dfrac{35}{10}=-2\)

c không rõ đề:v

= -5 / 7 x ( 2 / 11 + 9 / 11) + 12/7

= -5/7 x 1 + 12/7

= -5/7 + 12/7

= 1

b, = ( 9/4 x 105 - 9/4 x 101) : 3/2 - 64 x ( 1/4 - 3/4)

  =  [ 9/4 x ( 105 - 101)] : 3/2 -64 x -1/2

= 9/4 x 4 : 3 /2 - (-32)

= 9 : 3/2 + 32

= 18/3 +32

= 

a> 18.17-3.6.7

= 18.17-18.7

= 18 ( 17-7)

= 18.10 = 180

đi giải tiếp

giúp tớ với

-3^7.2^8/2^.3^7

=-3.2

=-6

5^3.3^5/5^3(0,5+2,5)

=5^3.3^5/5^3.3\

3^4

=81

5.7^4+7^3.25/7^5.125-7^3.50

=5.7^3(7+5

5.7^4+7^3.25/7^5.125-7^3.50

=5.7^4+7^3.5^2/7^5.5^3-7^3.11.5

=5.7^3(1.7+1.5)/7^3.5(7^2.25-11)

12/1250

\(-\frac{3}{5}.\frac{11}{7}+\frac{3}{-5}.\frac{4}{7}+\frac{23}{7}\)

\(=\frac{-3}{5}\left(\frac{11}{7}+\frac{4}{7}\right)+\frac{23}{7}\)

\(=\frac{-3}{5}.\frac{15}{7}+\frac{23}{7}\)

\(=\frac{-9}{7}+\frac{23}{7}=2\)

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