от Knowledge Greedy » 29 Ное 2015, 20:51
[tex]4^{x} - 3^{x-1/2} = 3^{x+1/2} - 2^{2x-1}[/tex]
[tex]4^{x} - 3^{-1/2}3^{x} =3^{1/2} 3^{x} - 2^{-1}2^{2x}[/tex]
[tex]4^{x} - \frac{1}{3^{1/2}}.3^{x} =\sqrt{3}.3^{x} - \frac{1}{2}.4^{x}[/tex]
[tex]4^{x} - \frac{1}{\sqrt{3}}.3^{x} =\sqrt{3}.3^{x} - \frac{1}{2}.4^{x}[/tex]
[tex]4^{x} + \frac{1}{2}.4^{x} =\sqrt{3}.3^{x} + \frac{\sqrt{3}}{3}.3^{x}[/tex]
[tex]\frac{3}{2}.4^{x} =\left ( \sqrt{3}+ \frac{ \sqrt{3}}{3}\right ).3^{x}[/tex]
[tex]\frac{4^{x}}{3^{x}} = \frac{8\sqrt{3}}{9}[/tex]
[tex]\left (\frac{4}{3} \right )^{x}= \frac{8\sqrt{3}}{9} \,\ (\ast)[/tex]
[tex]x=log_{ \frac{4}{3}}\frac{8\sqrt{3}}{9}=\frac{3}{2}[/tex]
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Отговорът се вижда по-ясно, ако [tex](\ast)[/tex] представим така [tex]\left ( \frac{2}{\sqrt{3}} \right )^{2x}=\left ( \frac{2}{\sqrt{3}} \right )^{3}[/tex]
Feci, quod potui, faciant meliora p0tentes.
Сторих каквото можах, по-добрите по-добро да направят.