How do I determine if a function is increasing?

[Malga1968]

I am having difficultyfollowing my text book.

If I have a function: -3x + 3
I find the deriv = -3

Since -3 is a constant , would my answer be that the function is not increasing at all?

thank you for any help.
M

 

[o_O]

Nope. It tells you that the function is a decreasing one as it has a constant negative slope.