2log11x=log^2 11 x-3
Log₁₁x = t (x>0) 2t - t² + 3 = 0 t² - 2t - 3 = 0 По т. Виета t₁ = 3, t₂ = -1 a) log₁₁x = 3 x = 11³ = 1331 б) log₁₁x = -1 x = 11⁻¹ = 1/11