Câu 1
\(x^3-2x^2+3x-6< 0\\ \Leftrightarrow x^2\left(x-2\right)+3\left(x-2\right)< 0\\ \Leftrightarrow\left(x-2\right)\left(x^2+3\right)< 0\\ \Leftrightarrow\left\{{}\begin{matrix}x-2< 0\Leftrightarrow x>2\\x^2+3< 0\Leftrightarrow x^2< 0\Leftrightarrow x\in\varnothing\end{matrix}\right.\)
S = {x/x>2}
câu 1 : tách 6=2.3
Câu 2: tách -4x = -3x-x
Câu 3 tách x= 2x-3x