Bài 1:
Xét: $(x^{100}+y^{100})^{2}=(12,18)^{2}$
$\Leftrightarrow 2x^{100}y^{100}=(12,18)^{2}-x^{200}-y^{200}=73,4074$
$\Leftrightarrow x^{100}y^{100}=36,7037$
$\Leftrightarrow x^{200}y^{200}=1347,161594$
Xét $(x^{200}+y^{200})^{2}=(74,945)^{2}$
$\Leftrightarrow...