kill(all)$

van=facebook.com/LearningCalculus$

f(x,y):=y^3+sqrt(8*x^4-2*y)-2*(2*x^4+3);

g(x,y):=sqrt(2*x^2+x+y) + 2*sqrt(x+2*y) - sqrt(9*x-2*x^2+19*y);

is(f( 1,2)=g( 1,2));
is(f(-1,2)=g(-1,2));