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Evaluate the following integral by reversing the order of integration:

∫₀¹∫_√(y)¹√(x³+1) d x d y

User Try
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Final answer:

The given double integral is evaluated by first understanding the integration region and then reversing the integration order, resulting in the integral ∫₀¹∫₀ₓ²√(x³+1) dy dx which can then be calculated.

Step-by-step explanation:

The student has asked to evaluate the double integral ∫₀¹∫ₙ¹√(x³+1) dxdy by reversing the order of integration. To do this, we first need to understand the region of integration in the xy-plane. The limits of the outer integral indicate that y ranges from 0 to 1. The limits of the inner integral tell us that for a given y, x ranges from √(y) to 1, which describes a region bounded by the line x=1, the x-axis, and the curve x=√(y).

When reversing the order of integration, we need to first describe this region in terms of x. The curve x=√(y), when solved for y, gives us y=x². Thus, the region can also be described by x ranging from 0 to 1 (since the square root of any y in the original region [0,1] will fall within [0,1]), and y ranging from 0 to x² for a given x.

The integral with the order of integration reversed is then ∫₀¹∫₀ₓ²√(x³+1) dy dx. We can now evaluate the inner integral with respect to y to obtain ∫₀¹x²√(x³+1) dx, followed by evaluating the resulting single-variable integral.

Evaluating the integral and reversing the order of integration are central to solving the problem, and involve understanding the region of integration.

User Mazen Harake
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