The Definition of the Derivative

​
The gray secant line joins the fixed red point on the graph of
y=f(x)
to a movable black point on the curve. Drag the black point along the curve. The slopes of the secant lines approximate the slope of the tangent line, which is the derivative of the function at
x
.

External Links

Derivative (Wolfram MathWorld)

Permanent Citation

Jim Swift
​
​"The Definition of the Derivative"​
​http://demonstrations.wolfram.com/TheDefinitionOfTheDerivative/​
​Wolfram Demonstrations Project​
​Published: September 28, 2007