restart;
F1:=x->x^2-2; F2:=x->x^2-1; F3:=x->x^2-1/2;
F4:=x->x^2; F5:=x->x^2+1/2; F6:=x->x^2+1;
F7:=x->x^2+2;







plot([F1(x),F2(x),F3(x),F4(x),F5(x),F6(x),F7(x)],
    x=-4..4);

G1:=x->(x-2)^2; G2:=x->(x-1)^2; G3:=x->(x-1/2)^2;
G4:=x->(x-0)^2; G5:=x->(x+1/2)^2; G6:=x->(x+1)^2;
G7:=x->(x+2)^2;







plot([G1(x),G2(x),G3(x),G4(x),G5(x),G6(x),G7(x)],
    x=-4..4);

H1:=x->-2*x^2; H2:=x->-1*x^2; H3:=x->(-1/2)*x^2;
H4:=x->(-1/4)*x^2; H5:=x->0*x^2; H6:=x->(1/4)*x^2;
H7:=x->(1/2)*x^2; H8:=x->1*x^2; H9:=x->2*x^2;









plot([H1(x),H2(x),H3(x),H4(x),H5(x),
    H6(x),H7(x),H8(x),H9(x)],x=-4..4);