Question

can u do me this equation integral of 1/cosx

Answer 1

\[\int\limits_{-1}^{1}1/cosxdx\]

Answer 2

this one can be tricky
rewrite it by multiplying by sec+tan on top and bottom
\[\rightarrow \frac{1}{\cos x}*\frac{\sec x +\tan x}{\sec x +\tan x} = \frac{\sec^{2} x + \sec x \tan x}{\sec x +\tan x}\]
make substitution
u = sec x + tan x
du = sec *tan + sec^2 dx
\[\rightarrow \int\limits_{-1}^{1} \frac{1}{u} du = \ln(u) = \ln(\sec x +\tan x)\]