Originally Posted by

**hamnet** Is it true that "y" can never be a negative number? and "x" can be postive or negative?

Okay, if I was asked to find the domain and range, input the function in my TI-83, graphed it, and then opened the table of values... Let's say: the following functions:

y=2.1(0.75)^x... If I opened the table of values, for any value of "x", "y" is a positive number, I am guessing it goes to infinity without becoming a negative?

So.. what I am trying to ask is: for any value of "x" "y" must be greater than or equal to zero? or greater than zero?...

Let's say: y = .5x^2 - .5x - 10 ?????