a)
(x-16)(x^2-2x+1)=0
(x-16)(x-1)^2=0
x-16=0 \vee x-1=0
x=16\vee x=1 pierwiastek dwukrotny
b)
(x+2)(x-1)(x^2-3x+2)=0
(x+2)(x-1)(x^2-3x+2)=0
(x+2)(x-1)(x^2-2x-x+2)=0
(x+2)(x-1)[x(x-2)-(x-2)]=0
(x+2)(x-1)(x-2)(x-1)=0
(x+2)(x-2)(x-1)^2=0
x+2=0\vee x-2=0 \vee x-1=0
x=-2 \vee x=2\vee x=1 pierwiastek dwukrotny
c)
(x^2-6x+5)(x^2+6x+5)=0
(x^2-5x-x+5)(x^2+5x+x+5)=0
[x(x-5)-(x-5)][x(x+5)+(x+5)]=0
(x-5)(x-1)(x+5)(x+1)=0
x-5=0\vee x-1=0\vee x+5=0\vee x+1=0
x=5\vee x=1\vee x=-5\vee x=-1
d)
8x(2-x)^2(x^2+6x-7)=0
8x=0\vee 2-x=0 \vee x^2+6x-7=0
x=0\vee x=2 \vee
x^2+7x-x-7=0
x(x+7)-(x+7)=0
(x+7)(x-1)=0
x=-7\vee x=1
x=-7\vee x=-1 \vee x=0\vee x=2