\(5\cdot8^x-2^{3x+1}=192\Leftrightarrow5.2^{3x}-2^{3x+1}=192\Leftrightarrow2^{3x}\cdot\left(5-2\right)=192\)
\(\Leftrightarrow2^{3x}\cdot3=192\Leftrightarrow2^{3x}=\frac{192}{3}=64=2^6\Leftrightarrow x=3\)
Vậy x=3.
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5.8x-23x+1=192
5.(23)x-23x+1=192
5.23x-23x+1=192
23x.(5-2)=192
23x.3=192
23x=192/3=64
23x=26
suy ra 3x=6; x=2
Vậy x=2
\(5.8^x-2^{3x+1}=192\)
<= \(5.2^{3x}-2^{3x}.2=192\)
<=> \(2^{3x}.\left(5-2\right)=192\)
<=> \(2^{3x}=64\)
<=> \(2^{3x}=2^6\)
<=> \(3x=6\)
<=> \(x=2\)
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