Suppose
f '(x) = xe^−x^2

Explanation:

You should find that the derivative is entirely negative whenever x < 0. This suggests that the function f(x) is decreasing on this interval. So that takes care of part (b).

The interval x < 0 is the same as -infinity < x < 0 which then translates to the interval notation (-infinity, 0)

Similarly, you should find that the derivative is positive when x > 0. So the function is increasing on the interval (0, infinity)

x= -3

step-by-step explanation:

step 1: simplify brackets

4 - x - 1 = 6

step 2: simpilfy

3 - x = 6

step 3: subtract 3 from both sides

-x = 6 - 3

step 4: simpilfy 6 - 3

-x = 3

step 5: multiply both sides by -1

x = -3

(x+3)(x+7)

step-by-step explanation: