1) (x+2)(x-3)<0x₁ = - 2x₂ = 3 + - +---------------------------------------------------------> -2 3 x x ∈ (- 2; 3)2) (x-4)(x+3)\<0x₁ = - 3x₂ = 4 + - +-------------------------------------------------------------------> -3 4 xx ∈ (-3; 4)3) x(2-x)>0x(x - 2) < 0x₁ = 0x₂ = 2 + - +-------------------------------------------------------------------------------> 0 2 xx ∈ (0; 2)4) 0.4x(7-x)(x-0,8)\<00.4x(x - 7)(x-0,8) > 0x₁ = 0x₂ = 0,8x₃ = 7 - + - +-------------------------------------------------------------------> 0 0,8 7 x x ∈ (0; 0,8) (7; + ∞)