Question

(3x-2)(x+1)=3x(x-3)

Answer 1

\(\left(3x-2\right)\left(x+1\right)=3x\left(x-3\right)\)

\(\Leftrightarrow3x^2+3x-2x-2=3x^2-9x\)

\(\Leftrightarrow3x^2-3x^2+3x-2x+9x=2\)

\(\Leftrightarrow10x=2\)

\(\Leftrightarrow x=\dfrac{1}{5}\)

Vậy \(S=\left\{\dfrac{1}{5}\right\}\)

Answer 2

(3x-2)(x+1)=3x(x-3)

⇔3x²+3x-2x-2=3x²-9x

⇔3x²-3x²+x-9x=2

⇔-8x=-2

⇔x=4

vậy pt có tập no S={4}