Question

Find the two x - intercepts of the function f and show that f ' (x) = 0 at some point between the two x - intercepts.

f (x) = x √(x + 4)

Answer 1

Step 1:

The function

Find  the -intercepts by substituting .

Apply zero product property.

and

-intercepts are and .

Step 2:

Product rule in derivatives .

Step 3:

Find the zeros of .

is zero between the -intercepts of at .

Solution:

-intercepts are and .

.