Evaluate: `int1/(sinx+cosx)\ dx`

Explanation

`int1/(sinx+cosx)\ dx`

`=int frac{sin^2x}{sinxcosx}+frac{cos^2x}{sinx cosx}dx`

`=int tanx+ cotx dx`

`=log secc+(-log cosecx)+C`

`=log abs(tan x)+C`