Помогите упростить выражение.

Решите задачу:

$[ \frac{2}{x^{1/4}-y^{1/4}} + \frac{2}{x^{1/4}+y^{1/4}} ]* \frac{x^{-1/2}-y^{-1/2}}{6x^{-1/4}y^{-1/2}} =\\$

$=2* \frac{x^{1/4}+y^{1/4}+x^{1/4}-y^{1/4}}{(x^{1/4}-y^{1/4})(x^{1/4}+y^{1/4})}* \frac{x^{1/4}y^{1/2}(x^{-1/2}-y^{-1/2})}{2*3} =\\$

$= \frac{1}{3} * \frac{x^{1/4}+y^{1/4}+x^{1/4}-y^{1/4}}{(x^{1/4}-y^{1/4})(x^{1/4}+y^{1/4})}* \frac{x^{1/4}y^{1/2}(y^{1/2}-x^{1/2})}{x^{1/2}y^{1/2}}=\\$

$= -\frac{1}{3} * \frac{2x^{1/4}}{x^{1/2}-y^{1/2}}* \frac{x^{1/4}y^{1/2}(x^{1/2}-y^{1/2})}{x^{1/2}y^{1/2}}=\\$

$= -\frac{1}{3} * \frac{2}1}* \frac{1}{1}=- \frac{2}{3}$