Calculus Course/Rate of Change

Rate of Change

Rate of Change is used to describe the ratio of a change in one variable compare to a change of another variable

If there is a function $f(x)=y$ then the rate of change of the function $f(x)$ correspond to the rate of change of variable z is

$\frac{\mathrm{\Delta }y}{\mathrm{\Delta }x}=\frac{\mathrm{\Delta }f(x)}{\mathrm{\Delta }x}$

Example

If there are two points $(1,3)$ and $(2,7)$

$\frac{\mathrm{\Delta }y}{\mathrm{\Delta }x}=\frac{\mathrm{\Delta }f(x)}{\mathrm{\Delta }x}=\frac{7-3}{2-1}=4$