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∫[0 to 2] ∫[0 to 1] 3(x + 4y)² dx dy =?

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Final answer:

To solve the given double integral, evaluate the integral with respect to the inner variable x and then the outer variable y. The final result is 6.17.

Step-by-step explanation:

To solve the given double integral, we first need to evaluate the integral with respect to the inner variable x and then the outer variable y. Let's start with the inner integral:

∫ [0 to 2] 3(x + 4y)² dx

Integrating this expression with respect to x, we get: 3/3 (x + 4y)³, evaluated from 0 to 2:

(1/3)[(2 + 4y)³ - (0 + 4y)³] = (1/3)(8 + 12y + 6y² + 8y + 4y² + y³) - (4y³) = (1/3)(8 + 20y + 10y² + y³)

Now, we can integrate this expression with respect to y:

∫ [0 to 1] (1/3)(8 + 20y + 10y² + y³) dy

Integrating this expression, we get: (8/3)y + (10/3)y² + (5/2)y³ + (1/12)y⁴, evaluated from 0 to 1:

(8/3) + (10/3) + (5/2) + (1/12) = 6.17

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