Помогите плиз, даю 30 балов
2x^2-5x-1=0;
D=25-4×2×(-1)=25+8=33
x1=(5-sqrt33)/4
x2=(5+sqrt33)/4
Проверим:
По теорема Виета
x1+x2=-(b/a)=5/2
x1+x2=(5-sqrt33)/4+(5+sqrt33)/4=5/4+5/4=5/2
x1×x2=c/a=-1/2
x1×x2=(5-sqrt33)/4×(5+sqrt33)/4=
=(25-33)/16=-8/16=-1/2