Log3(54-2x^2+x^2*3^x)=x+3
Log3(54-2x^2+x^2*3^x) = x+3 -> 3^(x+3) = 54-2x^2+x^2*3^x -> 27*3^x - 54 = x^2*3^x - 2x^2 -> 27*3^x = x^2*3^x -> x^2 = 27 и второе равенство - 54 = - 2x^2 -> x^2 = 27 x^2 = 27 -> x = 3√3