Bài 2:
a: \(x^2\left(x+3\right)-4\left(x+3\right)=0\)
\(\Leftrightarrow\left(x+3\right)\left(x-2\right)\left(x+2\right)=0\)
hay \(x\in\left\{-3;2;-2\right\}\)
b: \(\left(3x-1\right)^2=\left(2x+5\right)^2\)
\(\Rightarrow\left(3x-1-2x-5\right)\left(3x-1+2x+5\right)=0\)
\(\Leftrightarrow\left(x-6\right)\left(5x+4\right)=0\)
hay \(x\in\left\{6;-\dfrac{4}{5}\right\}\)
c: \(4x^2\left(x-1\right)-x+1=0\)
\(\Leftrightarrow\left(x-1\right)\left(2x-1\right)\left(2x+1\right)=0\)
hay \(x\in\left\{1;\dfrac{1}{2};-\dfrac{1}{2}\right\}\)
d: \(\Leftrightarrow\left(x+7\right)\left(5x-3\right)-\left(x-7\right)\left(x+7\right)=0\)
\(\Leftrightarrow\left(x+7\right)\left(5x-3-x+7\right)=0\)
\(\Leftrightarrow\left(x+7\right)\left(4x+4\right)=0\)
=>x=-7 hoặc x=-1
