0 \\ \frac{2}{3}^{cosx} = 1 \\ \frac{2}{3}^{cosx} = \frac{2}{3}^{0} \\ cosx = 0 \\ x = \frac{\pi }{2} + \pi n, " alt=" \frac{4}{9}^{cosx}+2* \frac{2}{3}^{cosx} - 3 = 0 \\ \frac{2}{3}^{2cosx}+2* \frac{2}{3}^{cosx} - 3 = 0 \\ a^{2} + 2a - 3 = 0 \\ a_{1}+a_{2} = -2 \\ a_{1}*a_{2} = -3 \\ a_{1} = -3 \\ a_{2} = 1 \\ \frac{2}{3}^{cosx} = -3 \\ \frac{2}{3}^{cosx} > 0 \\ \frac{2}{3}^{cosx} = 1 \\ \frac{2}{3}^{cosx} = \frac{2}{3}^{0} \\ cosx = 0 \\ x = \frac{\pi }{2} + \pi n, " align="absmiddle" class="latex-formula">
Не обращай внимания на эти А. Что-то пошло не так:)