Deleting task u are not using to save battery
Hi Trevon, you can use any one of a number of "task killers" available at the Google Play store to do exactly what you want here, although in my experience you would be much better off doing other things to conserve battery life.
Task killers have been shown to take up as much if not more battery life than they aim to help you save, so instead you should look into other methods to prolong your battery's charge. These include using the lowest brightness setting that's convenient on the screen, disabling the wireless antennas when you're not using them, and setting the auto-sleep interval to the shortest time possible.
Try those and see if they make a difference.