Odpowiedź:
zadanie 1
x=3, x=-3
zadanie 2
[tex] {3x}^{4} - 12 {x}^{2} = 0 \\ {x}^{2} (3 {x}^{2} - 12) = 0 \\ x = 0 \: \\ 3 {x}^{2} = 12 \\ {x}^{2} = 4 \\ x = 2[/tex]
[tex] {x}^{3} - {8x}^{2} + 15x = 0 \\ x( {x}^{2} - 8x + 15) = 0 \\ x = 0 \\ delta = 64 - 60 = 4 \\ x1 = 8 \\ x2 = 8[/tex]
zadanie 3
a)
[tex] {x}^{3} + {3x}^{2} - 4x - 12 = 0 \\ {x}^{2} (x + 3) - 4(x + 3) = 0 \\ (x + 3)( {x}^{2} - 4) = 0 \\ (x + 3)(x - 2)(x + 2) \\ x = 3 \ \ \ x = 2 \: \: \: x = - 2[/tex]
b)
[tex]{12x}^{3} - {5x}^{2} + 12x - 5 = 0 \\ {x}^{2} (12x - 5) + (12x - 5) = 0 \\ x = 0 \: \: \: x = \frac{5}{12} [/tex]
c i d sorry nie wiem
