This was common and well known even in the mid 90's with the TI-82. So much so that when my high school calculus class mostly bombed a test, the instructor aske

This was common and well known even in the mid 90's with the TI-82. So much so that when my high school calculus class mostly bombed a test, the instructor asked us how we could have possibly failed his test when we were all using "notes" on our calculator.