Use the formula below to find the instantaneous rate of change of the function at the given x-value. f(x)=6x2+6x at x=5 Average and Instantaneous Rate of Change 1 From the text, the instantaneous rate of change of the function f(x) is lim W h-I'O . Substituting f(x) = 6x2 + 6x into this formula and getting rid of the parentheses, we have the following. 2 _ 2 \"m f(X + h) f(x) \"m 6(X + h) + 6( |:| ) (6x + 6X) h-o h 1530 H on >