ACT Preparation / Unit 10 ACT 0912 short lesson, about 20 seconds
Average Rate of Change
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The idea
The average rate of change of f from a to b is (f(b) − f(a))/(b − a): the slope of the line joining those two points of the graph.
In practice
f(x) = x²: from 1 to 4, (16 − 1)/(4 − 1) = 5.
Where people slip
For a line, the average rate is the slope everywhere; for a curve, it depends on the interval.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
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