Rozwiąż równania a) 2(x-1)+x=x-3(2-3x) b) 2x²-10x-12=0 c) 3x³+3x²-12x-12=0

a) 2(x-1)+x=x-3(2-3x) 2x - 2 + x = x - 6 + 9x 2x + x - x -9x = 2 - 6 7x = 4 |:7 x = (4/7) b) (równanie kwadratowe więc wyliczamy: Δ, x₁ i x₂) 2x²-10x-12=0 a = 2 b = -10 c = -12 Δ = b² - 4ac Δ = 100 - 4 * 2 * -12 Δ = 100 + 96 (minus razy minus daje+) Δ = 196 √Δ = 14 x₁ = -b - √Δ / 2a = 10 - 14 / 4 = -4/4 = -1 x₂ = -b + √Δ / 2a = 10 + 14 / 4 = 24/4 = 6 c) 3x³ + 3x² - 12x - 12 = 0 3x² * ( x + 1 ) - 12 * ( x + 1 ) = 0 ( 3x² - 12 ) * ( x + 1 ) = 0 3 * ( x² - 4 ) * ( x + 1 ) = 0 3 *( x - 2 ) * ( x + 2 ) * ( x + 1 ) = 0 x₁ = -2 x₂ = -1 x₃ = 2 licze na naj ;)

a) 2(x-1)+x=x-3(2-3x) 2x - 2 + x = x - 6 + 9x 3x - x -9x = - 6 + 2 -7x = -4 |:(-7) x = 4/7 b)2x²-10x-12=0 Δ = b² - 4ac Δ = (-10)² - 4 * 2 * (-12) Δ = 100 + 96 Δ = 196 √Δ =√196 √Δ = 14 x₁ = 10 - 14 / 4 = -4/4 = -1 x₂ = 10 + 14 / 4 = 24/4 = 6 c) 3x³ + 3x² - 12x - 12 = 0 3x²( x + 1 ) - 12( x + 1 ) = 0 ( 3x² - 12 )( x + 1 ) = 0 3 ( x² - 4 ) * ( x + 1 ) = 0 3( x - 2 )( x + 2 )( x + 1 ) = 0 x₁ = 2 x₂ = -2 x₃ = -1