f(x,y) = (x^2+sin(exp y))/(sin (exp x)+(y^2))
f(x,y) = sin x . sin y
f(x,y) = sin x . sin y {jiné rozlišení}
f(x,y) = x^2 . y^2
f(x,y) = (x^2 + y^3) / (x^3 + y^3)
f(x,y) = (x^2 + y^3) / (x^3 + y^3) {detailněji}
f(x,y) = (x^2+exp sin(y))/(sin x+sin(y^2))
f(x,y) = (x^2+exp sin(y))/(sin x+sin(y^2)) {detailněji}
f(x,y) = x^4 + x^3.y + y^3.x + y^4