Question

Determinati numarul natural x stiind ca:

Answer 1

Răspuns:

$\dysplaystyle\bf\\a)\:(\frac{2}{3})^{x} = \frac{16}{81} \\\\(\frac{2}{3})^{x} = (\frac{2}{3})^{4} \Rightarrow \boxed{\dysplaystyle\bf\\ x= 4}\\\\b)\:(\frac{1}{7})^{x} = \frac{2}{98} \\\\(\frac{1}{7})^{x} = \frac{1}{49}\\\\(\frac{1}{7})^{x} = (\frac{1}{7})^{2} \Rightarrow \boxed{\dysplaystyle\bf\\ x= 2}\\\\c)\:(\frac{3}{2})^{x} = \frac{225}{100} \\\\(\frac{3}{2})^{x} = \frac{9}{4}\\\\(\frac{1}{7})^{x} = (\frac{3}{2})^{2} \Rightarrow \boxed{\dysplaystyle\bf\\ x= 2}$