2^(x+2) - 1/2^(1-x) = 56

Виносим за скобки 2^(x-1) * (1 - 2 + 2^2) = 56
Тогда 2^(x-1) = 56 / 3
x = 1 + log2(56 / 3)
x = log2(112/3)