$x=\frac{\pi}{2}-y\Rightarrow dx=-dy$
$x=0$ için $y=\frac{\pi}{2}$ ve $x=\frac{\pi}{2}$ için $y=0$ olur. O halde
$$I=\int_{\frac{\pi}{2}}^{0}\dfrac{\sqrt[3]{\sin^2(\frac{\pi}{2}-y)}}{\sqrt[3]{\sin^2(\frac{\pi}{2}-y)}+\sqrt[3]{\cos^2(\frac{\pi}{2}-y)}}(-dy)=\int_{0}^{\frac{\pi}{2}}\dfrac{\sqrt[3]{\cos^2y}}{\sqrt[3]{\cos^2y}+\sqrt[3]{\sin^2y}}dy$$
$$\Rightarrow$$
$$2I=\int_{0}^{\frac{\pi}{2}}\left(\dfrac{\sqrt[3]{\sin^2y}}{\sqrt[3]{\sin^2y}+\sqrt[3]{\cos^2y}} + \dfrac{\sqrt[3]{\cos^2y}}{\sqrt[3]{\cos^2y}+\sqrt[3]{\sin^2y}}\right)dy=\int_{0}^{\frac{\pi}{2}}dy=\frac{\pi}{2}$$
$$\Rightarrow$$
$$I=\frac{\pi}{4}$$