mình không bieets làm

\(10⋮\left(x+5\right)\)

\(\Rightarrow x+5\in\left\{-1;1;-2;2;-5;5;-10;10\right\}\)

\(\Rightarrow x\in\left\{-6;-4;-7;-3;-10;0;-15;5\right\}\left(x\in Z\right)\)

Để 10 ⋮ (x+5) thì (x+5) ∈ Ư(10)

⇒ (x+5) ∈ \(\left\{\pm1;\pm2;\pm5;\pm10\right\}\)

⇒ x ∈ {5;0;-3;-4;-6;-7;-10;-15}

\(b,\left(5x-1\right)^2:2=8\\ \Leftrightarrow\left(5x-1\right)^2=16\\ \Leftrightarrow\left[{}\begin{matrix}5x-1=4\\5x-1=-4\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=1\\x=-\dfrac{3}{5}\end{matrix}\right.\\ c,\left(1-3x\right)^3=-64\\ \Leftrightarrow1-3x=-4\\ \Leftrightarrow3x=5\\ \Leftrightarrow x=\dfrac{5}{3}\)

a) \(\left(2x-1\right)^3-4x^2\left(2x-3\right)=5\)

\(\Leftrightarrow8x^3-12x^2+6x-1-8x^3+12x^2=5\)

\(\Leftrightarrow6x-1=5\Leftrightarrow6x=6\Leftrightarrow x=1\)

b) \(\left(x+1\right)^3-\left(x-1\right)^3-6\left(x+1\right)^2=-10\)

\(\Leftrightarrow\left(x+1-x+1\right)\left[\left(x^2+2x+1+x^2-2x+1+\left(x^2-1\right)\right)\right]-6\left(x^2+2x+1\right)=-10\)

\(\Leftrightarrow2\left(3x^2+1\right)-6x^2-12x-6=-10\)

\(\Leftrightarrow6x^2+2-6x^2-12x-6=-10\)

\(\Leftrightarrow-12x-4=-10\Leftrightarrow12x=-6\Leftrightarrow x=\dfrac{1}{2}\)

a) \(\dfrac{11}{2}=\dfrac{10+1}{2}=5+\dfrac{1}{2}\)

\(\dfrac{32}{9}=\dfrac{27+5}{9}=3+\dfrac{5}{9}< 5+\dfrac{1}{2}\)

Vậy \(\dfrac{11}{2}>\dfrac{32}{9}\)

b)\(\dfrac{100}{23}=\dfrac{92+8}{23}=4+\dfrac{8}{23}\)

 \(\dfrac{302}{123}=\dfrac{246+56}{123}=2+\dfrac{56}{123}< 4+\dfrac{8}{23}\)

Vậy \(\dfrac{100}{23}>\dfrac{302}{123}\)

c) \(\dfrac{515}{605}< \dfrac{515+1}{605+1}=\dfrac{516}{606}\Rightarrow\dfrac{515}{605}< \dfrac{516}{606}\)

24,05 m = 24m 5cm

Vì 24m = 24 m 

1m=100cm nên 0,05 x100 = 5 cm 

24,05m=24m5cm

bởi vì 24m=24m;0,5m=5cm

a, Thời điểm này, nhiều học sinh đang tập trung ôn mốc điểm 9-10.

Giữa lòng thành phố Đà Lạt, có một quán cháo lòng bán rất ngon.

\(...=\dfrac{3}{2}x\dfrac{4}{3}x\dfrac{5}{4}x\dfrac{6}{5}x\dfrac{7}{6}....x\dfrac{1000}{999}\)

\(=\dfrac{1}{2}x\dfrac{1000}{1}=500\)

=3/2x4/3x5/4x....x1000/999

=1/2x1000=500

mình chưa chắc là đúng đâu nhé

Nửa chu vi:

\(2\dfrac{5}{6}:2=1\dfrac{5}{12}=\dfrac{17}{12}\left(m\right)\)

Chiều dài:

\(\left(\dfrac{17}{12}+\dfrac{1}{2}\right):2=\dfrac{23}{24}\left(m\right)\)

Chiều rộng:

\(\dfrac{17}{12}-\dfrac{23}{24}=\dfrac{11}{24}\left(m\right)\)

Diện tích:

\(\dfrac{23}{24}\times\dfrac{11}{24}=\dfrac{253}{576}\left(m^2\right)\)

nửa chu vi:2 5/6:2=17/12(m)

chiều rộng:(17/12-1/2);2=11/24(m)

chiều dài:17/12-11/24=23/24(m)

diện tich miếng bìa:11/24x23/24=253/576(m2)

B=243/729+81/729+27/727+9/727+3/727+1/727=364/727

B=243/729+81/729+27/727+9/727+3/727+1/727=364/727