Question

помогите решить,пожалуйста

Answer 1

$7 {}^{2x} \times 7 {}^{3} - 2 {}^{2x} \times 2 {}^{6} - 3 \times 7 {}^{2x} \times {}^{2} + 2 {}^{2x} \times 2 {}^{3} = 0 \\ 7 {}^{2x} \times 343 - 2 {}^{2x} \times 64 - 3 \times 7 {}^{2x} \times 49 + 2 {}^{2x} \times 8 = 0 \\ 343 \times 7 {}^{2x} - 64 \times 2 {}^{2x} - 147 \times 7 {}^{2x} + 8 \times 2 {}^{2x} = 0 \\ 196 \times 7 {}^{2x} - 56 \times 2 {}^{2x} = 0 \\ 196 \times 7 {}^{2x} = 56 \times 2 {}^{2x} \\ 196 \times ( \frac{7}{2} ) {}^{2x} = 56 \\ ( \frac{7}{2} ) {}^{2x} = \frac{2}{7} \\ ( \frac{7}{2} ) {}^{2x} = ( \frac{7}{2} ) {}^{ - 1} \\ 2x = - 1 \\ x = - \frac{1}{2}$