\(5^{3x+3}\le10^{18}:8^6\)
\(\Leftrightarrow5^{3x+3}\le\left(2.5\right)^{18}:\left(2^3\right)^6\)
\(\Leftrightarrow5^{3x+3}\le2^{18}.5^{18}:2^{18}\)
\(\Leftrightarrow5^{3x+3}\le5^{18}\)
\(\Leftrightarrow3x+3\le18\)
\(\Leftrightarrow3x\le15\)
\(\Leftrightarrow x\le5\)
Vậy \(x\le5\)
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