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Website
Cool Math

Coolmath: More on Tangent Lines

For Students 9th - 10th
This CoolMath resource provides instruction and practice for tangent lines.
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Graphic
Mathematics Archives

Math Archives: Visual Calculus: Graph a Function, Its Second Derivative

For Students 9th - 10th
This online tutorial site shows that the concavity of a function is related to the second derivative of the function by using an online graphing system. Inflection points are also briefly discussed.