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A) Start with the integral Iₙ = ∫ from 0 to 2 of (x² + 4)ⁿ dx, and find Aₙ and Bₙ such that Iₙ₊₁ = AₙIₙ + Bₙ.

b) Using the results from part (a), or otherwise, evaluate the integral ∫ from 0 to 2 of (x² + 4)⁸ dx.

c) If Simpson's rule on four subintervals is used to approximate π = ∫ from 0 to 2 of (x² + 4)/8 dx, find the approximation.

User Mdhale
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1 Answer

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Final answer:

To solve the given parts, one must establish a recursive formula between Iᵢ₊₁ and Iᵢ, and use it for simplifying the evaluation of I₈. Then, apply Simpson's rule with the given function and intervals to approximate π.

Step-by-step explanation:

To answer part (a) of the question, let's consider the expression for I₍₊₁ which involves the integral of (x² + 4) raised to the power (n+1). If we expand this expression in terms of I₍, we can try to identify coefficients A₍ and B₍ such that:

I₍₊₁ = A₍ I₍ + B₍

To do this, look for a relationship between (x² + 4) raised to the n and (n+1) powers that would allow for the integral to be expressed in terms of I₍ directly or through differentiation/integration by parts.

For part (b), you must use the relationship found in part (a) repeatedly to simplify the calculation of the integral with n=8. Basic algebra and calculus techniques will be used to evaluate I₈.

In part

, Simpson's rule approximation of π involves dividing the interval from 0 to 2 into four equal subintervals and then applying the Simpson's rule formula:

π ≈ ¾·[(f(0)+4f(½)+2f(1)+4f(1 ½)+f(2))]

Where f(x) = (x² + 4)/8. Finally, plugging in the values of f(x) at the points x = 0, ½, 1, 1 ½ and 2 will yield the Simpson's rule approximation of π.

User Crezzur
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