Bài 64: I = $ \int_{3\pi/4}^{\pi/2}(tan^2x - tanx)e^{-x}dx $
Bài 65: I = $ \int_{0}^{\pi/6}\frac{tan(x - \frac{\pi}{4})}{cos2x}dx $
Bài 7: I = $ \int_{0}^{\pi/2}\frac{sinx{cos^3}x}{1 + {cos^2}x}dx $
Bài 9: I = $ \int_{-\pi/3}^{\pi/3}\frac{\sqrt{3} + tanx}{\sqrt{3} - tanx}dx $
Bài 11: I = $ \int_{0}^{\pi/2}\frac{sin2x + sinx}{\sqrt{1 + 8cosx}}dx $
Bài 12: I = $ \int_{0}^{\pi/6}\frac{dx}{cosxcos(x + \frac{\pi}{4})} $
