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Find the average rate of change of the function f(x)=2x^3-x from [4,6].

PLEASE HELP!

User Bearzk
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2 Answers

6 votes

Answer:

151

Explanation:

Average Rate of Change Formula


(f(b)-f(a))/(b-a)\\(f(6)-f(4))/(6-4) \\(((2*6^3)-6)-((2*4^3)-4))/(2) \\((432-6)-(128-4))/(2) \\(426-124)/(2)\\\\ (302)/(2) = 151

If you have trouble remembering the rate of change formula, it's the same as the slope formula.


f(b) = y_2\\f(a) = y_1\\b = x_2\\b = x_1\\slope = (y_2-y_1)/(x_2-x_1) \\

Similarly to the slope formula, it doesn't matter which point you set up to be the second coordinate, as long as it is consistent across the numerator and denominator.

User Timm Kent
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7.4k points
2 votes

The average rate of change of a function f(x) over the interval [a, b] is given by the formula:

average rate of change = (f(b) - f(a)) / (b - a)

In this case, the function is f(x) = 2x^3 - x and the interval is [4, 6]. So we have:

f(4) = 2(4)^3 - 4 = 124

f(6) = 2(6)^3 - 6 = 330

Therefore, the average rate of change of f(x) over [4, 6] is:

(330 - 124) / (6 - 4) = 103

So the average rate of change of the function f(x) over the interval [4, 6] is 103.

User Will Holley
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7.4k points