Question

\(3x^2+7x+2=0\)

Answer 1

\(3x^2+7x+2=0\)

\(\Leftrightarrow3x^2+x+6x+2=0\)

\(\Leftrightarrow x\left(3x+1\right)+2\left(3x+1\right)=0\)

\(\Leftrightarrow\left(3x+1\right)\left(x+2\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}3x+1=0\\x+2=0\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=-\dfrac{1}{3}\\x=-2\end{matrix}\right.\)

\(S=\left\{-\dfrac{1}{3},-2\right\}\)

Answer 2

\(3x^2+7x+2=0\)

\(3x^2+6x+x+2=0\)

\(3x\left(x+2\right)+\left(x+2\right)=0\)

\(\left(3x+1\right)\left(x+2\right)=0\)

=>\(x+2=0=>x=-2\)

hoặc \(3x+1=0=>x=\dfrac{-1}{3}\)

Answer 3

3x² + 7x + 2 = 0

<=> 3x² + 6x + x + 2 = 0

<=> (3x + 1)(x + 2) = 0

<=> x = -1/3 hoặc x = -2

Answer 4

   3x² + 7x +2 = 0

△ = 7² - 4.3.2 

△ = 49 - 24

△ = 25 > 0

-> phương trình có 2 nghiệm phân biệt

x1 = (-7 + 5)/6 = -1/3

x2 = (-7-5)/6 = -2

Answer 5

nhiều bạn trả lời câu hỏi giúp mình quéee.Cảm ưnn mí bạn nhaaa<3