Решите уравнения, сгруппировав члены и разложив на множители: 1) x³ + x² = 20x 2) x + 1 = 9x³ +9x² 3) 4y³ - 2 = y - 8y² 4) 2x - 3 = 8x³ - 12x² 5) x³ + 2x² - 9x = 18 6) 9y³ + 8= 4y + 18y² 7) 3x³ + 2x² = 12x + 8 8) 4x³ - 12x² = 9...

1) x³ + x² = 20x⇒1) x³ + x² - 20x=0⇒x(x²+x-20)=0⇒x(x+5)(x-4)=0⇒x₁=0; x₂=-5; x₃=4 2) x + 1 = 9x³ +9x²⇒2) x + 1 -( 9x³ +9x²)=0⇒x+1-9x²(x+1)=0⇒ (x+1)(1-9x²)=0⇒(x+1)(1-3x)(1+3x)=0⇒x₁=-1; x₂=1/3; x₃=-1/3 3) 4y³ - 2 = y - 8y²⇒3) 4y³ - 2 - y + 8y²=0⇒4y²(y+2)-(y+2)=0⇒(y+2)(4y²-1)=0⇒ (y+2)(2y-1)(2y+1)=0⇒y₁=-2; y₂=1/2; y₃=-1/2 4) 2x - 3 = 8x³ - 12x²⇒4) 2x - 3 - (8x³ - 12x²)=0⇒2x-3-4x²(2x-3)=0⇒ (2x-3)(1-4x²)=0⇒(2x-3)(1-2x)(1+2x)=0⇒x₁=3/2; x₂=1/2; x₃=-1/2 5) x³ + 2x² - 9x = 18⇒5) x³ + 2x² - 9x - 18=0⇒x²(x+2)-9(x+2)=0⇒ (x+2)(x²-9)=0⇒(x+2)(x-3)(x+3)=0⇒x₁=-2; x₂=3; x₃=-3 6) 9y³ + 8= 4y + 18y²⇒6) 9y³ + 8- 4y - 18y²=0⇒9y²(y-2)-4(y-2)=0⇒ (y-2)(9y²-1)=0⇒(y-2)(3y-1)(3y+1)=0⇒y₁=2; y₂=1/3; y₃=-1/3 7) 3x³ + 2x² = 12x + 8⇒7) 3x³ + 2x² - 12x - 8=0⇒x²(3x+2)-4(3x+2)=0⇒ (3x+2)(x²-4)=0⇒(3x+2)(x+2)(x-2)=0⇒x₁=-2/3; x₂=-2; x₃=2 8) 4x³ - 12x² = 9x - 27⇒8) 4x³ - 12x² - 9x + 27=0⇒4x²(x-3)-9(x-3)=0⇒ (x-3)(4x²-9)=0⇒(x-3)(2x-3)(2x+3)=0⇒x₁=3; x₂=3/2; x₃=-3/2