The illustration shows the function f(x)= x^3+ 2x^2 and its derivative f'(x)= 3x^2 +4x.
The graph is available as a threshold copy for blind students (8 point Braille) and as a graph for visually impaired students.

In each case 3 different versions exist:

• Function
• 1st derivativ
• Function and 1st derivative

Hint: It makes sense to mark the vertex points on the swell copy with a pin.