\(A=\frac{17^{20}+2}{17^{20}-1}=\frac{17^{20}-1+3}{17^{20}-1}=1+\frac{3}{17^{20}-1}\)

\(B=\frac{17^{20}-2}{17^{20}-5}=\frac{17^{20}-5+3}{17^{20}-5}=1+\frac{3}{17^{20}-5}\)

Vì \(17^{20}-1>17^{20}-5\)

\(=>\frac{3}{17^{20}-1}1+\frac{3}{17^{20}-1}

d) Ta có: \(32\%-0.25:x=-\dfrac{17}{5}\)

\(\Leftrightarrow0.25:x=\dfrac{8}{25}+\dfrac{17}{5}=\dfrac{93}{25}\)

hay \(x=\dfrac{25}{372}\)

Vậy: \(x=\dfrac{25}{372}\)

e) Ta có: \(\left(x+\dfrac{1}{5}\right)^2+\dfrac{17}{25}=\dfrac{26}{25}\)

\(\Leftrightarrow\left(x+\dfrac{1}{5}\right)^2=\dfrac{9}{25}\)

\(\Leftrightarrow\left[{}\begin{matrix}x+\dfrac{1}{5}=\dfrac{3}{5}\\x+\dfrac{1}{5}=-\dfrac{3}{5}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{2}{5}\\x=-\dfrac{4}{5}\end{matrix}\right.\)

Vậy: \(x\in\left\{\dfrac{2}{5};-\dfrac{4}{5}\right\}\)

f) Ta có: \(-\dfrac{32}{27}-\left(3x-\dfrac{7}{9}\right)^3=-\dfrac{24}{27}\)

\(\Leftrightarrow\left(3x-\dfrac{7}{9}\right)^3=\dfrac{-8}{27}\)

\(\Leftrightarrow3x-\dfrac{7}{9}=-\dfrac{2}{3}\)

\(\Leftrightarrow3x=\dfrac{1}{9}\)

hay \(x=\dfrac{1}{27}\)

g) Ta có: \(60\%\cdot x+0.4x+x:3=2\)

\(\Leftrightarrow\dfrac{4}{3}x=2\)

hay \(x=\dfrac{3}{2}\)

Vậy: \(x=\dfrac{3}{2}\)

h) PT \(\Leftrightarrow\left|\dfrac{20}{9}-x\right|=\dfrac{2}{9}\) \(\Rightarrow\left[{}\begin{matrix}\dfrac{20}{9}-x=\dfrac{2}{9}\\x-\dfrac{20}{9}=\dfrac{2}{9}\end{matrix}\right.\) \(\Leftrightarrow\left[{}\begin{matrix}x=2\\x=\dfrac{22}{9}\end{matrix}\right.\)

  Vậy ...

i) PT \(\Leftrightarrow\dfrac{8}{5}+\dfrac{2}{5}x=\dfrac{16}{5}\) \(\Leftrightarrow\dfrac{2}{5}x=\dfrac{8}{5}\) \(\Leftrightarrow x=4\)

  Vậy ...

x+8/10=340/360-324/360

x+8/10=16/360

x=16/360-80/360

x=-64/360

x-1/10=1/15

x=1/15+1/10

x=10/150-15/150

x=-5//150=-1/30

(3/5-2)+13/20=5/6

(3/5-10/5)+13/20

-7/5+13/20=5/6

tính nhanh à bạn mik ko hiểu

giúp mik đang vội :)

a. 19/17      b) 2

\(a)\dfrac{6}{17}+\dfrac{3}{17}\)

\(=\dfrac{6+13}{17}\)

\(=\dfrac{19}{17}\)

\(b)5\times\dfrac{8}{20}\)

\(=5\times\dfrac{2}{5}\)

\(=\dfrac{10}{5}\)

\(=2\)

_HT_

x^2=16

Suy ra x^2=4^2

Vậy x^2=4^2

[1/(x+2)-1/(x+5)]+[1/(x+5)-1/(x+10)]+[1/(x+10)-1/(x+17)]=x/15.[1/(x+2)-1/(x+17)]
1/(x+2)-1/(x+17)=x/15.[1/(x+2)-1/(x+17)]
1=x/15
x=15

sdsdxc

a)\(\left(\dfrac{3}{5}+\dfrac{17}{21}\right)^2\)

b)4

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