Question: For positive a, consider the family of functions
y = arctan (√x + √a), x > 0
(1 - √ax)
(a) Graph several curves in the family and describe how the graph changes as a varies.
(b) Use a computer algebra system to find dy/dx, and graph the derivative for several values of a. What do you notice?
(c) Do your observations in part (b) agree with the answer to part (a)? Explain.