SOLUTION: Find the area between y = x^3−81 x and the x-axis

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Question 972717: Find the area between y = x^3−81 x and the x-axis
Answer by Alan3354(69443) About Me  (Show Source):
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Find the area between y = x^3 - 81 x and the x-axis
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x-ints at -9, 0 & +9
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f(x) = x^3 - 81x
INT(x) = x^4/4 - 81x^2/2 (Ignore the C)
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INT(9) = 6561/4 - 6561/2 = -6561/4
INT(0) = 0
Area above the x-axis = 6561/4 sq units
Area below = 6561/4
Total bounded area = 6561/2 sq units