The Secant Line

Drag point Q closer to point P. Watch what happens to the line!

Tangent Line!

Naming the Parts

Drag the mathematical expressions to match their visual meaning on the graph.

{{ target.label }} {{ target.desc }}
Drop here

Build the Definition

Drag the pieces to assemble the formal definition of the derivative.

Finding the Tangent Line

Slide towards 0 to find the exact slope, then pick the equation.

Function:
Point :
{{ row.x_h }} {{ row.fx_h }} {{ row.slope }}

Select the correct tangent line equation:

Brilliant!

You've mastered the definition of the derivative and found the tangent line.