\(5\frac{9}{10}:\frac{3}{2}-\left(2\frac{1}{3}x4\frac{1}{2}-2\frac{1}{2}\right):\frac{7}{4}\)

=\(\frac{59}{10}:\frac{3}{2}-\left(\frac{7}{3}x\frac{9}{2}-\frac{5}{2}\right):\frac{7}{4}\)

=\(\frac{118}{30}-\left(\frac{63}{6}-\frac{5}{2}\right)x\frac{4}{7}\)

=\(\frac{118}{30}-\left(\frac{63}{6}-\frac{15}{6}\right)x\frac{4}{7}\)

=\(\frac{118}{30}-8x\frac{4}{7}\)

=\(\frac{118}{30}-\frac{32}{7}\)

sau bn tự tính nha

\(A=\frac{3469-54}{6938-108}\)

\(=\frac{3415}{6830}\)

\(=\frac{3415}{6830}=\frac{3415:3415}{6830:3415}=\frac{1}{2}=\frac{3}{6}\)

\(B=\frac{2468-89}{3720-147}\)

\(=\frac{2370}{3555}\)

\(=\frac{2370}{3555}=\frac{2370:1185}{3555:1185}=\frac{2}{3}=\frac{4}{6}\)

bn ơi còn C,D

các bn lm đến đâu cx dc miễn là lm hộ mk cái ạ, ai đang lm vào nhắn tin vs mk để mk bít nha

a; \(-\dfrac{8}{3}+\dfrac{7}{5}-\dfrac{71}{15}< x< -\dfrac{13}{7}+\dfrac{19}{14}-\dfrac{7}{2}\)

              -\(\dfrac{19}{15}\) - \(\dfrac{71}{15}\) < \(x\) < -\(\dfrac{1}{2}\) - \(\dfrac{7}{2}\)

              -6 < \(x\) < -4

             vì \(x\) \(\in\) Z nên \(x\) = -5

- \(\dfrac{19}{6}+\dfrac{-15}{2}+\dfrac{11}{3}\) < \(x\) < - \(\dfrac{5}{4}\) + \(\dfrac{19}{12}\) - \(\dfrac{10}{3}\)

- \(\dfrac{32}{3}+\dfrac{11}{3}< x< \) \(\dfrac{1}{3}\) - \(\dfrac{10}{3}\)

-7 < \(x\) < - 3

Vì \(x\in\) Z nên \(x\in\) {-6;-5;-4}

x=17 nhé

mk kô bt đánh ps đâuu à

a) x+30%x=-1.31

=> 100%x+30%x=-1.31

=>x.(100%+30%)=-1.31

=>x.13/10=-1.31=-1.31:13/10=-131/130

b) (x-1/2):1/3+5/7=9+5/7

=>(x-1/2).3+5/7=68/7

=>(x-1/2).3=68/7-5/7=9

=>x-1/2=9:3=3

=>x=3+1/2=3 1/2( hỗn số)

c) 1/2x-3/4=14/9.3/7

=>1/2x-3/4=2/3

=>1/2x=2/3+3/4=17/12

x=17/12:1/2=17/12.2=17/6

d) - 5/6 -x = 7/12+ -1/3

=>- 5/6 -x = 7/12+ -4/12=1/4

=> x = -5/6 -1/4=-13/12

e) x + 3/-15 = 1/3

=> x= 1/3 - -3/15 =1/3+3/15

=> x=5/15 + 3/15=8/15

f) (4,5 -2 x). (-1 4/7)=11/14

=> 4,5 -2x=11/14 : -3/7=11/14. -7/3=-11/6

=>-2x=-11/6-9/2= -11/6 -27/6 =-19/3

=>x= -19/3: -2x=19/6

Chúc bn thi HKII tốt!!!

ban hoc truong nao vay ? de cua ban giong cua minh lam

bạn học trường j mà giống đề bài mình zay

\(\frac{2}{3}+\frac{8}{35}< \frac{x}{105}< \frac{1}{7}+\frac{2}{5}+\frac{1}{3}\)

\(\frac{94}{105}< \frac{x}{105}< \frac{92}{105}\)

\(\Rightarrow94< x< 92\)

mà x là số tựu nhiên => \(x\in\varnothing\)

S=1-1/4+1-1/9+...+1-1/x²

S=(1+1+1+...+1)-(1/4+1/9+...+1/x²)

Có (1/4+1/9+...+1/x²)<1/(1.2)+1/(2.3)+...+1/(x-1)x=1-1/x<1

=> (1/4+1/9+...+1/x²) ko là số nguyên

=>S ko là số nguyên

           \(4.B=\frac{4}{1.5}+\frac{4}{5.9}+\frac{4}{9.13}+...+\frac{4}{93.97}\) 

            \(4.B=1-\frac{1}{5}+\frac{1}{5}-\frac{1}{9}+\frac{1}{9}-\frac{1}{13}+...+\frac{1}{93}-\frac{1}{97}\)

            \(4.B=1-\frac{1}{97}\)

             \(4.B=\frac{96}{97}\)

                 \(B=\frac{96}{97}:4\)

                 \(B=\frac{24}{97}\)