Let fx8x2 Find a value A such that the average rateof change
Let f(x)=8x^2.
Find a value A such that the average rateof change of f(x) from 1 to A equals 88.
Solution
Average = [f(A)-f(1)]/[A-1]
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88 = [8A^2 - 8]/[A-1]
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8A^2 - 8 = 88A - 88
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A^2 -1 = 11A - 11
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A^2 - 11A + 10 = 0
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(A-10)(A-1) = 0
A = 10 or A = 1
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Reasonable solution:
A = 10
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![Let f(x)=8x^2. Find a value A such that the average rateof change of f(x) from 1 to A equals 88.SolutionAverage = [f(A)-f(1)]/[A-1] --- 88 = [8A^2 - 8]/[A-1] -- Let f(x)=8x^2. Find a value A such that the average rateof change of f(x) from 1 to A equals 88.SolutionAverage = [f(A)-f(1)]/[A-1] --- 88 = [8A^2 - 8]/[A-1] --](/WebImages/26/let-fx8x2-find-a-value-a-such-that-the-average-rateof-change-1067319-1761558511-0.webp)