Wyznacz wielomian $v(x, y) = [u(x, y)]^2 - 2w(x, y)$.
a) $u(x, y) = 2x^2 - xy$, $w(x, y) = 6x^3y^2 - 3x^2y^2 + y^4$
b) $u(x, y) = 3x^2y + 2xy^2$, $w(x, y) = 2x^4y^4 + 3x^3y^3 - xy^4 + 4x^2y^2$
c) $u(x, y) = xy + y^2$, $w(x, y) = x^2y^2 - 2xy^3$
d) $u(x, y) = x^2 - 3y$, $w(x, y) = 2x^4 + x^2y - 4y^2$
e) $u(x, y) = \frac{1}{2}xy^2 + 2x^2$, $w(x, y) = x^2y^4 + 3x^3y^2 - 2x^4$
f) $u(x, y) = -y^3 + 4x$, $w(x, y) = -y^6 + 5xy^3 + 8x^2$