- #1

- 40

- 0

[itex]\int \! \left( {e^{x}}+{e^{-x}} \right) ^{-1}{dx}[/itex]

I tried integration by parts... I ended up getting [itex]\left( {e^{x}} \right) ^{-1}[/itex] even thought the right answer, according to Maple and my graphing calculator is [itex]\arctan \left( {e^{x}} \right)[/itex]

I then tried using substitution... I made [itex]u={e^{x}}[/itex] and then [itex]{\it du}={e^{x}}{\it dx}[/itex] but that doesn't help me, because I don't have [itex]{e^{x}}{\it dx}[/itex] but rather I have [itex]{\frac {{\it dx}}{{e^{x}}}}.[/itex]

Can anyone point me in the right direction? Thanks!