1. $\int 0 \, dx = C$
2. $\int x^n \, dx = \frac{x^{n+1}}{n+1} + C$,其中 $n \neq -1$
3. $\int \frac{1}{x} \, dx = \ln|x| + C$
4. $\int a^x \, dx = \frac{a^x}{\ln(a)} + C$
5. $\int e^x \, dx = e^x + C$
6. $\int \sin x \, dx = -\cos x + C$
7. $\int \cos x \, dx = \sin x + C$
8. $\int \frac{1}{\cos^2 x} \, dx = \tan x + C$
9. $\int \frac{1}{\sin^2 x} \, dx = -\cot x + C$
10. $\int \frac{1}{\sqrt{1-x^2}} \, dx = \arcsin x + C$
11. $\int \frac{1}{1+x^2} \, dx = \arctan x + C$
12. $\int \frac{1}{a^2-x^2} \, dx = \frac{1}{2a} \ln \left| \frac{a+x}{a-x} \right| + C$
13. $\int \sec x \, dx = \ln| \sec x + \tan x | + C$
14. $\int \frac{1}{a^2+x^2} \, dx = \frac{1}{a} \arctan \left( \frac{x}{a} \right) + C$
15. $\int \frac{1}{\sqrt{a^2-x^2}} \, dx = \arcsin \left( \frac{x}{a} \right) + C$
16. $\int \sec^2 x \, dx = \tan x + C$
这些公式涵盖了幂函数、对数函数、指数函数、三角函数、反三角函数等基本初等函数的积分。在实际应用中,这些公式可以帮助我们快速求解定积分。