Предмет: Математика, автор: ramix058

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Автор ответа: Pandovna

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${9}^{x} - 2 \times {3}^{x} = 63 \\ {3}^{2x} - 2 \times {3}^{x} - 63 = 0 \\ {3}^{x} = t \\ {t}^{2} - 2t - 63 = 0 \\ d = 4 + 4 \times 63 = 256 \\ t1 = \frac{2 - 16}{2} = - 7 \\ t2 = \frac{2 + 16}{2} = 9 \\ { 3 }^{x} = - 7 \\ {3}^{x} = 9 = {3}^{2} \\ x = 2$

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