+136 Consider the function f(x) = 2x^3 - 15x^2 - 36x + 6 on the interval [-4 ,7]. Find the average or mean slope of the function on this interval.
+130071 As before
f(7) = 2(7)^3 -15(7)^2 - 36(7) + 6 = -295
f(-4) = 2(-4)^3 -15(-4)^2 -36 (-4) + 6 = -218
Avg slope = f(7) - f(-4) -295 - -218
_________ = __________ = -77/11 = -7
7 - -4 11
f '(x) = 6x^2 -30x -36
So
6x^2 -30x -36 = -7
6x^2 -30x - 29 = 0
Using the Quadratic formula
x≈-0.82916
x≈5.8292
