A personal anecdote about why I ask you to read your new calculator's instruction manual before using it:
In college, I was taking an introductory Electrical Engineering course which dealt primarily with the basics of circuits and such. Our second test of the semester (we only had two tests, so this was a biggie) required you to use complex algebra to solve all of the problems. Now, complex algebra is not difficult, rather its a pain in the ass, meticulous and time consuming. So I heard that the bookstore was selling this new calculator (HP x46 or something like that) that performed complex algebra with the press of a button. Sweet! I was able to convince my parents to cough up $100 so I could run down to the store and buy one of these technological wonders. I picked one up, and sure enough - it performed complex algebra with the press of a button. I took the test the next day (which was rather easy) in record time.
When I received the test back and my score was 5 out of 100, I realized that I had been pressing the WRONG BUTTON during the entire test. Damn. Drop class, do not collect $200, go directly to the Registrar's office.
Please - learn from my mistakes and read the manual (RTFM!). One more request - no "you stupid asshole" comments; I know it was retarded.