log₈ x +log√₂ x = 14
Перейдем к основанию 2:
$$\frac{log₂ x}{log₂ 8} + \frac{log₂ x}{log₂ 2^{1/2}} = 14$$
$$\frac{log₂ x}{3} + \frac{log₂ x}{1/2} = 14$$
$$\frac{log₂ x}{3} + 2log₂ x = 14$$
$$\frac{log₂ x + 6log₂ x}{3} = 14$$
$$7log₂ x = 42$$
$$log₂ x = 6$$
$$x = 2^6$$
$$x = 64$$
Ответ: x = 64