tìm x a/(2x ²-3x)=0 b/4+3x ²/x-3 – 2x+2x ²/x-3 + 2x-13/x-3 =0 càn gấp 30/11/2021 Bởi Lydia tìm x a/(2x ²-3x)=0 b/4+3x ²/x-3 – 2x+2x ²/x-3 + 2x-13/x-3 =0 càn gấp
a) $2x^2-3x=0$ $⇔x.(2x-3)=0$ $⇔$\(\left[ \begin{array}{l}x=0\\2x-3=0\end{array} \right.\) $⇔$\(\left[ \begin{array}{l}x=0\\2x=3\end{array} \right.\) $⇔$\(\left[ \begin{array}{l}x=0\\x=\dfrac{3}{2}\end{array} \right.\) b) $\dfrac{4+3x^2}{x-3}-\dfrac{2x+2x^2}{x-3}+\dfrac{2x-13}{x-3}=0$ $⇔\dfrac{4+3x^2-2x-2x^2+2x-13}{x-3}=0$ $⇔\dfrac{x^2-9}{x-3}=0$ $⇔\dfrac{(x-3)(x+3)}{x-3}=0$ $⇔x+3=0$ $⇔x=-3$ Bình luận
Đáp án: `a) 2x^2-3x=0` `⇒ x.(2x-3)=0` `⇒` \(\left[ \begin{array}{l}x=0\\2x-3=0\end{array} \right.\) `⇒`\(\left[ \begin{array}{l}x=0\\2x=3\end{array} \right.\) `⇒`\(\left[ \begin{array}{l}x=0\\x=\dfrac{3}{2}\end{array} \right.\) `b)(4+3x^2)/(x-3)-(2x+2x^2)/(x-3)+(2x-13)/(x-3)=0` `⇒ (4+3x^2-2x-2x^2+2x-13)/(x-3)=0` `⇒ (x^2-9)/(x-3)=0` `⇒((x-3)(x+3))/(x-3)=0` `⇒x+3=0` `⇒x=-3` Bình luận
a) $2x^2-3x=0$
$⇔x.(2x-3)=0$
$⇔$\(\left[ \begin{array}{l}x=0\\2x-3=0\end{array} \right.\)
$⇔$\(\left[ \begin{array}{l}x=0\\2x=3\end{array} \right.\)
$⇔$\(\left[ \begin{array}{l}x=0\\x=\dfrac{3}{2}\end{array} \right.\)
b) $\dfrac{4+3x^2}{x-3}-\dfrac{2x+2x^2}{x-3}+\dfrac{2x-13}{x-3}=0$
$⇔\dfrac{4+3x^2-2x-2x^2+2x-13}{x-3}=0$
$⇔\dfrac{x^2-9}{x-3}=0$
$⇔\dfrac{(x-3)(x+3)}{x-3}=0$
$⇔x+3=0$
$⇔x=-3$
Đáp án:
`a) 2x^2-3x=0`
`⇒ x.(2x-3)=0`
`⇒` \(\left[ \begin{array}{l}x=0\\2x-3=0\end{array} \right.\)
`⇒`\(\left[ \begin{array}{l}x=0\\2x=3\end{array} \right.\)
`⇒`\(\left[ \begin{array}{l}x=0\\x=\dfrac{3}{2}\end{array} \right.\)
`b)(4+3x^2)/(x-3)-(2x+2x^2)/(x-3)+(2x-13)/(x-3)=0`
`⇒ (4+3x^2-2x-2x^2+2x-13)/(x-3)=0`
`⇒ (x^2-9)/(x-3)=0`
`⇒((x-3)(x+3))/(x-3)=0`
`⇒x+3=0`
`⇒x=-3`