1)3^(х+2) + 3^х = 303^х ·3^2 + 3^х = 303^х ·9 + 3^х = 303^х ·(9 + 1) = 3010·3^х = 303^х = 3x = 1 2) 2/(lgx-3) + 4/(lgx+1) = 1ОДЗ: lgx ≠ 3, lgx ≠ 1, х > 02·(lgx+1)/((lgx-3)·(lgx+1)) + 4·(lgx-3)/((lgx+1)(lgx-3)) = ((lgx+1)(lgx-3))/((lgx+1)(lgx-3))2·(lgx+1) + 4·(lgx-3) = (lgx+1)(lgx-3)2lgx + 2 + 4lgx -12 = lg²x + lgx - 3lgx - 36lgx -10 = lg²x - 2lgx - 3 lg²x - 8lgx + 7 = 0Замена: у = lgx у² - 8у + 7 = 0D = 64 - 28 = 36√D = 6y₁ = (8 - 6):2 = 1y₂ = (8 + 6):2 = 7Возвращаемся к замене1) 1 = lgxх₁ = 102) 7 = lgxх₂ = 10⁷ = 10 000 000