ACT Preparation / Unit 11 ACT 1016 short lesson, about 20 seconds
Maximum and Minimum
Captions available
The idea
A parabola's vertex gives its extreme value: a minimum when it opens up, a maximum when it opens down. The value is the vertex's y-coordinate.
In practice
f(x) = −2x² + 8x has its maximum at x = 2, where f(2) = 8.
Where people slip
Answer the question asked: where the maximum occurs is x = 2; what the maximum is, 8.
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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