p(x2+y2)=x(p2+q2)p\left(x^{2}+y^{2}\right)=x\left(p^{2}+q^{2}\right)p(x2+y2)=x(p2+q2)
q2(x2+y2)=p2(p2+q2)q^{2}\left(x^{2}+y^{2}\right)=p^{2}\left(p^{2}+q^{2}\right)q2(x2+y2)=p2(p2+q2)
q(x2+y2)=y(p2+q2)q\left(x^{2}+y^{2}\right)=y\left(p^{2}+q^{2}\right)q(x2+y2)=y(p2+q2)
p(x2+y2)=y(p2+q2)\mathrm{p}\left(\mathrm{x}^{2}+\mathrm{y}^{2}\right)=\mathrm{y}\left(\mathrm{p}^{2}+\mathrm{q}^{2}\right)p(x2+y2)=y(p2+q2)