Evaluate the integral.
Recall Fubini's Theorem. The double integral of a continuous function f(x, y) over a rectangle R = [a, b] × [c, d] is equal to the iterated integral (in either order):
The function is not continuous only at x = .
Thus in the rectangle R = [0, 7] × [0, 4], f(x, y) continuous.
Apply Fubini's Theorem. We will chose to use the order of x first.
Where d = and b = .
Since the integrand can be written as the product of two functions f(x, y) = h(y)g(x), the double integral is the product of two single integrals.
Evaluate .
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Evaluate .
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Evaluate .
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