Question

`intdx/(secx+tanx)` is equal to ______.

Options

• log |secx + tanx| + C

• log |secx – tanx| + C

• log |1 + cosx| + C

• log |1 + sinx| + C

Answer 1

`intdx/(secx+tanx)` is equal to log |1 + sinx| + C.

Explanation:

`int1/(secx+tanx)xx(secx-tanx)/(secx-tanx)dx`

= `int(sec-tanx)/1dx`

= log|secx + tanx| – log|secx| + C

= `log|(secx+tanx)/secx|`

= log|1 + sinx| + C