nguyên hàm 12

Question

1 > $\int\limits\cos \left ( 3x-\frac{\Pi }{5} \right )dx$
2> $\int\limits\sin \left ( \frac{x}{2} +\frac{\Pi }{7}\right )dx$
3> $\int\limits\frac{dx}{\cos ^2(3x-1)}$

score 0 · Answer 1

Bình chọn tăng 0 Bình chọn giảm

$I_3 =\int \dfrac{dx}{\cos^2 (3x-1)} =\dfrac{1}{3}\int \dfrac{d(3x-1)}{\cos^2 (3x-1)} = \dfrac{1}{3}\tan (3x-1)+C$

score 0 · Answer 2

Bình chọn tăng 0 Bình chọn giảm

$I_1 =\int \cos (3x-\dfrac{\pi}{5}) dx = \dfrac{1}{3} \int \cos (3x-\dfrac{\pi}{5}) d(3x-\dfrac{\pi}{5}) =\sin (3x-\dfrac{\pi}{5}) + C$

$I_2 = \int \sin (\dfrac{x}{2}+\dfrac{\pi}{7}) dx =2\int \sin (\dfrac{x}{2}+\dfrac{\pi}{7}) \ d(\dfrac{x}{2}+\dfrac{\pi}{7}) =-2\cos (\dfrac{x}{2}+\dfrac{\pi}{7})+C$