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Find the least squares approximation of f(x) = x² over the interval [0, 2π] by a trigonometric polynomial of degree n.

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Final answer:

The student is required to approximate the function f(x) = x² on the interval [0, 2π] using a trigonometric polynomial of degree n by employing the least squares method, which minimizes errors through Fourier series components.

Step-by-step explanation:

The student is seeking to approximate a function f(x) = x² on the interval [0, 2π] with a trigonometric polynomial of degree n. This involves using the method of least squares, which minimizes the sum of the squares of the differences between the function values and the values of the approximating trigonometric polynomial. In particular, for a trigonometric polynomial of degree n, one needs to determine the coefficients that best represent the original function in terms of a basis of sines and cosines over the given interval. This process bypasses the need for solving quadratic equations and uses Fourier series components to achieve the approximation. The coefficients are usually found by setting up and solving a system of linear equations derived from the condition that the integral of the square of the difference between f(x) and the trigonometric polynomial over the interval is as small as possible.

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