Đáp án: $a,\left[ \begin{array}{l}x=2\\x=-1\end{array} \right.$ $b,x=2$ Giải thích các bước giải: $\begin{array}{l}a,|2x-1|=3\\→\left[ \begin{array}{l}2x-1=3\\2x-1=-3\end{array} \right.\\→\left[ \begin{array}{l}2x=4\\2x=-2\end{array} \right.\\→\left[ \begin{array}{l}x=2\\x=-1\end{array} \right.\\vậy \,\, x=2 \,\, hoặc \,\, x=-1\\b,(2x-1)^3=27\\→(2x-1)^3=3^3\\→2x-1=3\\→2x=4\\→x=2\\vậy \,\, x=2\\\underline{\text{CHÚC BẠN HỌC TỐT}}\\\end{array}$ Trả lời
$|2x-1| = 3$ $⇒$ \(\left[ \begin{array}{l}2x-1=3\\2x-1=-3\end{array} \right.\) $⇔$ \(\left[ \begin{array}{l}x=2\\x=-1\end{array} \right.\) Vậy $x$ $∈$ `{-1;2}`. `(2x-1)^3 = 27` `⇔ (2x-1)^3 = 3^3` `⇔ 2x – 1 =3` `⇔ 2x = 4` `⇔ x = 2` Vậy $x=2$. Trả lời
Đáp án:
$a,\left[ \begin{array}{l}x=2\\x=-1\end{array} \right.$
$b,x=2$
Giải thích các bước giải:
$\begin{array}{l}a,|2x-1|=3\\→\left[ \begin{array}{l}2x-1=3\\2x-1=-3\end{array} \right.\\→\left[ \begin{array}{l}2x=4\\2x=-2\end{array} \right.\\→\left[ \begin{array}{l}x=2\\x=-1\end{array} \right.\\vậy \,\, x=2 \,\, hoặc \,\, x=-1\\b,(2x-1)^3=27\\→(2x-1)^3=3^3\\→2x-1=3\\→2x=4\\→x=2\\vậy \,\, x=2\\\underline{\text{CHÚC BẠN HỌC TỐT}}\\\end{array}$
$|2x-1| = 3$
$⇒$ \(\left[ \begin{array}{l}2x-1=3\\2x-1=-3\end{array} \right.\)
$⇔$ \(\left[ \begin{array}{l}x=2\\x=-1\end{array} \right.\)
Vậy $x$ $∈$ `{-1;2}`.
`(2x-1)^3 = 27`
`⇔ (2x-1)^3 = 3^3`
`⇔ 2x – 1 =3`
`⇔ 2x = 4`
`⇔ x = 2`
Vậy $x=2$.