Date: 05/29/98 at 18:41:32
From: Ms. Curtis Basham's Math Class
Subject: y=x!
Our class was running a warm-up where the teacher forgot the function
cards, and we were making up our own functions when Nick Gilbertson
stumped the class. We were giving him values for x and he gave us
values back. Nick got perplexed when we gave him zero and negative
integers. We eventually discovered that his function was:
y = x!
Our teacher was so excited, and we guessed at what might be going on
when x = 0, x = -1, and so on. Using calculators, we received error
messages for negative integers but not for zero. Using the computer we
graphed y = x! and saw its unique graph.
Our questions: What is going on at x = -1, -2, -3, ... ? What is the
rule for factorial when x = 0? Zero times anything is zero, so why is
0! not zero? How do you calculate 0.5! rather than read it off a
graph? What about when x = -3.5?
Help,
Ms. Curtis Basham's 8th grade class