Variation of functions
Step (i) Move point A, along the curve
Step (ii) Identify the places where the function
(a) increases
(b) decreases
(c) does not increase nor decrease (remains stationary)
Step (iii) Activate the tangent checkbox
Step (iv) Drag point A to move the tangent along the curve
Step (v) Try tpo relate the bahavior of the tangent with the variation (increase/decrease/stationary) of the function