a)[latex]x^2 (x+3)-4(x+3)=0[/latex] [latex](x+3)(x^2 -4)=0[/latex] [latex](x+3)(x-2)(x+2)=0[/latex] [latex]x=-3[/latex] lub [latex]x=2[/latex] lub [latex]x=-2[/latex] b)[latex]5(x^3 -1)+21x(x-1)=0[/latex] [latex]5(x-1)(x^2 +x+1)+21x(x-1)=0[/latex] [latex](x-1)(5x^2 +5x+5+21x)=0[/latex] [latex](x-1)(5x^2 +26x+5)=0[/latex] [latex](x-1)*5(x+5)(x+1/5)=0[/latex] x=1 lub x=-5 lub x=-1/5 c)[latex]8x^3 (x^2 -4)-(x^2 -4)=0[/latex] [latex](x^2 -4)(8x^3 -1)=0[/latex] [latex](x-2)(x+2)((2x)^3 -1)=0[/latex] [latex](x-2)(x+2)(2x-1)(4x^2 +2x+1)=0[/latex] x=2 lub x=-2 lub x=1/2
a) x³+3x²-4x-12=0 x²(x+3)-4(x+3)=0 (x+3)(x²-4)=0 x+3=0 v x²-4=0 odp. x=-3 x=2 v x=-2 b)5x³+21x²-21x-5=0 x²(5x+21)-(5x+21)=0 (5x+21)(x²-1)=0 5x=-21 odp x=-4,25 v x=1 v x=-1 c)8x⁵-32x³-x²+4=0 8x³(x²-4)-(x²-4)=0 (x²-4)(8x³-1)=0 odp. x=2 v x=-2 v x=0,5