Calculus Course/Change in Variable

Change in Variable

A Change in variable is a term used to express the diffeence between 2 variables . Let ${\Delta}$ represents Change in 2 variables x0 and x then

$\Delta x = x - x_o$
$x = x_o + \Delta x$

If there is a function f(x) such that when x change by an amount ${\Delta} x$ the change in function will be

$\Delta f(x) = f(x) - f(x_o)$
$f(x) = f(x_o) + \Delta f(x)$

Example

There are 2 points (1,3) (5,7) then

$\Delta x = x - x_o = 5 - 1 = 4$
$\Delta f(x) = 7 - 3 = 4$