Đáp án:
$\begin{array}{l}
d){16^x} < {128^4}\\
\Rightarrow {\left( {{2^4}} \right)^x} < {\left( {{2^7}} \right)^4}\\
\Rightarrow {2^{4x}} < {2^{28}}\\
\Rightarrow 4x < 28\\
\Rightarrow x < 7\\
\text{Vậy}\,x < 7\\
e){5^x}{.5^{x + 2}} \le 1000000000000000000:{2^{18}}\\
\Rightarrow {5^{x + x + 2}} \le {10^{18}}:{2^{18}}\\
\Rightarrow {5^{2x + 2}} \le \left( {{2^{18}}{{.5}^{18}}} \right):{2^{18}}\\
\Rightarrow {5^{2x + 2}} \le {5^{18}}\\
\Rightarrow 2x + 2 \le 18\\
\Rightarrow 2x \le 16\\
\Rightarrow x \le 8\\
\text{Vậy}\,x \le 8
\end{array}$
