How do I completely get rid of a potentially compromising picture? I received a potentially compromising picture in a WhatsApp chat on my iPhone, I want to get rid of it entirely in everything Apple. 

I've deleted it from the chat (within minutes), but where else could it end up being stored? Photostream? Camera Roll? Somewhere in my Macbook? Would it be backed up to the iCloud automatically? Please tell me all the places I need to check to be sure. Sorry for the newbie questions.
I received a potentially compromising picture in a WhatsApp chat


So someone else sent it to you. 

If you delete the image from within the application, emptied the trash, checked your photo stream / iPhoto folders, deleted the contents of Library/Caches on any computers linked to the same service account, and checked Time Machine in the same locations it is highly unlikely that it still exists on your computer.

But someone else still has the original.

As many public figures have discovered, it's more-or-less impossible to permanently delete an image once someone else has it.