Question 61773
Evaluate:
7 
(8x^2 + 8x - 18) dx 
-4 
(2 decimal places) 
Evaluate:

F(x)=[(8/3)x^3+4x^2-18x] evaluated between x=-4 and x=7
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Comment: f(x) has zeroes at x=-2.08 and x=1.08
Evaluating F(x) between x=-4 and x=7 involves three definate
integrals:
Int from -4 to 7 = int from -4 to -2.08 minus int from x=-2.08
to x=1.08 plus Int x=1.08 to x=7
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This is a mess to evaluate so I'll leave it you.
--------------
Here is some of the arithmetic.
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F(7)=(8/3)(7^3)+4(7^2)-18(7)
=179148.67
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F(-4)=(8/3)(-4)^3+4(-4)^2-18(-4)
=-10850.67
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Cheers,
Stan H.

8 
(9x2 - 4x - 31) dx 
1 
(2 decimal places) 
The marginal cost function for producing x units of a certain product is given by:
C'(x) = 2 + 0.08x 
Find the total cost incurred by increasing the production level from 900 to 500 units. (2 decimal places) 
Find the average value of the function
f(x) = 4x3 - 6x over the interval [-4,9]. 
Evaluate:
7 
(7x - 5)4 dx 
-3 
(2 decimal places)