Question

Suppose the function G(t) represents a test grade (out of 100 points) as a function of hours studied. If
G(t)=-0.046t^3+0.915t^2+38.005 points, what is (dG/dt)when t=4? Round your answer to the nearest point per hour.


a. 50 points per hour

b. 3 points per hour

c. 5 points per hour

d. 7 points per hour

e. 20 points per hour

Answers

Writeacher
Your umpteen posts have been removed.

Once you write up <b>WHAT YOU THINK</b>, please re-post, and someone here will be happy to comment.
Roger
WHY ARE YOU DELETING MY POSTS?
Writeacher
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Anonymous
Derivative of t ^ 3 = 3 * t ^ 2

Derivative of t ^ 2 = 2 * t

Derivative of 38.005 = 0

dG / dt = - 0.046 * 3 * t ^ 2 + 0.915 * 2 t + 0 = - 0.138 * t ^ 2 + 1.83 * t

When t = 4

then :

dG / dt = - 0.138 * 4 ^ 2 + 1.83 * 4

dG / dt = - 0.138 * 16 + 7 . 32

dG / dt = - 2.208 + 7.32

dG / dt = 5.112


Rounded to the nearest point per hour :

dG / dt = 5 points per hour

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