$$\int_0^{\frac{\pi}{6}}secydy=\int_0^{\frac{\pi}{6}}\frac{1}{cosy}dy$$ olduğundan
$$tan\frac y2=u\Rightarrow \frac 12.(1+tan^2\frac y2)dy=du\Rightarrow dy=\frac{2.du}{1+u^2},\quad cos\frac y2=\frac{1-u^2}{1+u^2}$$ olcaktır.
Buradan $$\int_0^{2-\sqrt3}\frac{1+u^2}{1-u^2}.\frac{2}{1+u^2}du=2\int_0^{2-\sqrt3}\frac{1}{1-u^2}du$$
$$\int_0^{2-\sqrt3}\left[\frac{1}{1-u}+\frac{1}{1+u}\right]du=\left[ln|1-u^2|\right]_0^{2-\sqrt3}=ln(4\sqrt3-6)$$ olacaktır.