d, đk : x khác -2 ; 0
\(\Rightarrow2\left(x+2\right)-5x=3x\left(x+2\right)-3x^2\Leftrightarrow-3x+4=6x\)
\(\Leftrightarrow-9x=-4\Leftrightarrow x=\dfrac{4}{9}\left(tm\right)\)
e, đk : x khác -2 ; 0
\(\Rightarrow x^2-2\left(3x+6\right)=3x\left(3x+6\right)-24x^2\)
\(\Leftrightarrow x^2-6x-12=-15x^2+18x\Leftrightarrow16x^2-24x-12=0\)
\(\Leftrightarrow x=\dfrac{3\pm\sqrt{21}}{4}\)
d. ĐKXĐ: \(x\ne\left\{-2;0\right\}\)
\(\dfrac{2}{x}-\dfrac{5}{x+2}=3-\dfrac{3x}{x+2}\)
\(\Leftrightarrow2\left(x+2\right)-5x=3\left(x+2\right)x-3x^2\)
\(\Leftrightarrow2x+4-5x=3x^2+6x-3x^2\)
\(\Leftrightarrow4=9x\)
\(\Leftrightarrow x=\dfrac{4}{9}\)(TM)
e. ĐKXĐ: \(x\ne\left\{-2;0\right\}\)
\(\dfrac{x}{3x+6}-\dfrac{2}{x}=3-\dfrac{8x}{x+2}\)
\(\Leftrightarrow x^2-6\left(x+2\right)=9x\left(x+2\right)-24x^2\)
\(\Leftrightarrow x^2-6x-12=9x^2+18x-24x^2\)
\(\Leftrightarrow16x^2-24x-12=0\)
\(\Leftrightarrow\left[{}\begin{matrix}\dfrac{3+\sqrt{21}}{4}\\\dfrac{3-\sqrt{21}}{4}\end{matrix}\right.\left(TM\right)\)
d)\(Đk:x\ne0,x\ne-2\)
\(Pt\Rightarrow\dfrac{2\left(x+2\right)-5x}{x\left(x+2\right)}=\dfrac{3x\cdot\left(x+2\right)-3x^2}{x\left(x+2\right)}\)
\(\Rightarrow2x+4-5x=3x^2+6x-3x^2\)
\(\Rightarrow-3x+4=6x\Rightarrow x=\dfrac{4}{9}\left(tmđk\right)\)
