Tìm x ( 2x – 1 ) . ( 3x + 5 ) = 0 ( x – 1 )^2 = 9 22/07/2021 Bởi Reese Tìm x ( 2x – 1 ) . ( 3x + 5 ) = 0 ( x – 1 )^2 = 9
Đáp án: \(\left[ \begin{array}{l}x=\dfrac{1}{2}\\x=\dfrac{-5}{3} \end{array} \right.\) \(\left[ \begin{array}{l}x=4\\x=-2\end{array} \right.\) Giải thích các bước giải: `( 2x – 1 ) . ( 3x + 5 ) = 0``=>`\(\left[ \begin{array}{l}2x-1=0\\3x+5=0\end{array} \right.\) `=>`\(\left[ \begin{array}{l}2x=0+1\\3x=0-5\end{array} \right.\) `=>`\(\left[ \begin{array}{l}2x=1\\3x=-5\end{array} \right.\)`=>`\(\left[ \begin{array}{l}x=1:2\\x=-5:3\end{array} \right.\) `=>`\(\left[ \begin{array}{l}x=\dfrac{1}{2}\\x=\dfrac{-5}{3} \end{array} \right.\)`( x – 1 )^2 = 9``=>`\(\left[ \begin{array}{l}(x-1)^2=3^2\\(x-1)^2=(-3)^2\end{array} \right.\) `=>`\(\left[ \begin{array}{l}x-1=3\\x-1=-3\end{array} \right.\) `=>`\(\left[ \begin{array}{l}x=3+1\\x=-3+1\end{array} \right.\) `=>`\(\left[ \begin{array}{l}x=4\\x=-2\end{array} \right.\) Bình luận
Giải thích các bước giải: $(2x-1)(3x+5)=0$ $⇔$ \(\left[ \begin{array}{l}2x-1=0\\3x+5=0\end{array} \right.\) $⇔$ \(\left[ \begin{array}{l}2x=1\\3x=-5\end{array} \right.\) $⇔$ \(\left[ \begin{array}{l}x=\dfrac{1}{2}\\x=-\dfrac{5}{3}\end{array} \right.\) $\text{Vậy $x∈\{-\dfrac{5}{3};\dfrac{1}{2}\}$}$ $(x-1)^2=9$ $⇔(x-1)^2=(±3)^2$ $⇔$ \(\left[ \begin{array}{l}x-1=3\\x-1=-3\end{array} \right.\) $⇔$ \(\left[ \begin{array}{l}x=4\\x=-2\end{array} \right.\) $\text{ Vậy $x∈\{-2;4\}$}$ Học tốt!!! Bình luận
Đáp án:
\(\left[ \begin{array}{l}x=\dfrac{1}{2}\\x=\dfrac{-5}{3} \end{array} \right.\)
\(\left[ \begin{array}{l}x=4\\x=-2\end{array} \right.\)
Giải thích các bước giải:
`( 2x – 1 ) . ( 3x + 5 ) = 0`
`=>`\(\left[ \begin{array}{l}2x-1=0\\3x+5=0\end{array} \right.\)
`=>`\(\left[ \begin{array}{l}2x=0+1\\3x=0-5\end{array} \right.\)
`=>`\(\left[ \begin{array}{l}2x=1\\3x=-5\end{array} \right.\)
`=>`\(\left[ \begin{array}{l}x=1:2\\x=-5:3\end{array} \right.\)
`=>`\(\left[ \begin{array}{l}x=\dfrac{1}{2}\\x=\dfrac{-5}{3} \end{array} \right.\)
`( x – 1 )^2 = 9`
`=>`\(\left[ \begin{array}{l}(x-1)^2=3^2\\(x-1)^2=(-3)^2\end{array} \right.\)
`=>`\(\left[ \begin{array}{l}x-1=3\\x-1=-3\end{array} \right.\)
`=>`\(\left[ \begin{array}{l}x=3+1\\x=-3+1\end{array} \right.\)
`=>`\(\left[ \begin{array}{l}x=4\\x=-2\end{array} \right.\)
Giải thích các bước giải:
$(2x-1)(3x+5)=0$
$⇔$ \(\left[ \begin{array}{l}2x-1=0\\3x+5=0\end{array} \right.\) $⇔$ \(\left[ \begin{array}{l}2x=1\\3x=-5\end{array} \right.\) $⇔$ \(\left[ \begin{array}{l}x=\dfrac{1}{2}\\x=-\dfrac{5}{3}\end{array} \right.\)
$\text{Vậy $x∈\{-\dfrac{5}{3};\dfrac{1}{2}\}$}$
$(x-1)^2=9$
$⇔(x-1)^2=(±3)^2$
$⇔$ \(\left[ \begin{array}{l}x-1=3\\x-1=-3\end{array} \right.\) $⇔$ \(\left[ \begin{array}{l}x=4\\x=-2\end{array} \right.\)
$\text{ Vậy $x∈\{-2;4\}$}$
Học tốt!!!