Examples

Example 2.2.3  

$\displaystyle \int x^2 + 1 + \frac{1}{x^2 + 1} dx$ $\displaystyle = \int x^2dx + \int 1dx + \int \frac{1}{x^2+1} dx$    
  $\displaystyle = \frac{1}{3} x^2 + x + \tan^{-1}(x) + c.$    

Example 2.2.4  

$\displaystyle \int \sqrt{\frac{5}{x}} dx =
\int \sqrt{5} x^{-1/2} dx = 2\sqrt{5} x^{1/2} + c.
$

Example 2.2.5  

$\displaystyle \int \frac{\sin(2x)}{\sin(x)} dx = \int \frac{2\sin(x)\cos(x)}{\sin(x)}
= \int 2\cos(x) = 2\sin(x) + c
$



William Stein 2006-03-15