Question

Evaluate the following integral:

$\int {\sec }^{2}xdx$

• A. $2\tan x+C$
• B. $\tan 2x+C$
• C. $\tan x+C$
• D. None of these

Answer 1

Answer: (C)

$\tan x+C$

We know that.

$\frac{d}{dx}\left(\tan x\right)={\sec }^{2}x$

$\therefore d\left(\tan x\right)={\sec }^{2}xdx$

$\Rightarrow I=\int {\sec }^{2}xdx=\tan x+C$