(х-у)²-(х-у)=0⇒(х-у)9х-у-1)=0
1)х=у
x^4-x²-2=0
x²=a
a²-a-2=0
a1+a2=1 U a1*a2=-2
a1=-1⇒x²=-1-нет решения
a2=2⇒x²=2⇒x=+-√2 U y=+-√2
(-√2;-√2) (√2;√2)
2)x=y+1
y²(y+1)²-y(y+1)-2=0
y^4+2y³+y²-y²-y-2=0
y^4+2y³-y-2=0
y³(y+2)-(y+2)=0
(y+2)(y³-1)=0
y=-2⇒x=-1
y=1⇒x=2
(-1;-2) (2;1)
Ответ (-√2;-√2) (√2;√2) (-1;-2) (2;1)