d)(2x+5)4=4096
=>2x+5=8
=>2x=3
=>x=\(\dfrac{3}{2}\)
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c)(2x-3)2 =25
(2x-3)2=52
=>2x-3= 5
2x=5+3
2X=8
=>x= 4
d)(2x+5)4= 4096
(2x+5)4= 84
=> 2x+5 =8
2x= 8-5
2x= 3
=>x= 3: 2
X= 1,5
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c: Ta có: \(\left(2x-3\right)^2=25\)
\(\Leftrightarrow\left[{}\begin{matrix}2x-3=5\\2x-3=-5\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}2x=8\\2x=-2\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=4\\x=-1\end{matrix}\right.\)
d: Ta có: \(\left(2x+5\right)^4=4096\)
\(\Leftrightarrow\left[{}\begin{matrix}2x+5=8\\2x+5=-8\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}2x=3\\2x=-13\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{3}{2}\\x=-\dfrac{13}{2}\end{matrix}\right.\)
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