Average Rate Of Change Formula

[bwpbruce]

Is this the correct symbol to use for average rate of change:
\(\displaystyle \overline{\triangle}=\dfrac{f(b)-f(a)}{b-a} \)

 

[I like Serena]

The correct notation for average rate of change is:
$$\frac{\Delta f}{\Delta x} = \frac{f(b)-f(a)}{b-a}$$

 

[HallsofIvy]

I would say that Greg's example is the "standard" or "usual" symbol for rate of change and that there is no "correct" symbol for anything! As long as you define your notation, there is no "incorrect" notation.