Ответ:

Пошаговое объяснение:

y=x^2-5x+2;

x^2-5x-1=y-3

(x^2-5x+2)(x^2-5x-1)=28. =>y(y-3)=28 => y^2-3y-28=0 D=9+4*28=121 ;y=(3+11)/2=7 y=(3-11)/2=-4

1) x^2-5x+2=7;

2) x^2-5x+2=-4;

1) x^2-5x+2=7;

x^2-5x-5=0; D=25+20=45

x1=(5+3√5)/2; x2=(5-3√5)/2;

2) x^2-5x+2=-4;

x^2-5x+6=0; D=25-4*6=25-24=1;

 x3=(5+1)/2=3; x4=(5-1)/2=2;

x1=(5+3√5)/2;

x2=(5-3√5)/2;

x3=(5+1)/2=3;

x4=(5-1)/2=2;

x1*x2*x3*x4=((5+3√5)/2)((5-3√5)/2)*3*2=-5*6=-30