qqp question1: How do I integrate [math]\displaystyle\int_{\frac\pi6}^{\frac\pi4}\sqrt{1-\cos2x}\,dx[/math]? question2: How do I evaluate the integral [math]\int_{-\pi/4}^{\pi/4} (\frac{\pi}4-x)^n \sec x\,dx[/math]?