ind the Taylor series expansion of f(x) = e^(x²) centered at x=0x = 0 and determine its interval of convergence.

Answer: The Taylor series expansion of f(x)=ex2f(x) = e^{x^2} centered at x=0x = 0 is ∑n=0∞x2nn!=1+x2+x42!+x63!+…\sum_{n=0}^{\infty} \frac{x^{2n}}{n!} = 1 + x^2 + \frac{x^4}{2!} + \frac{x^6}{3!} + \dots. The interval of convergence is (−∞,∞)(-\infty, \infty).

Step-by-step solution

Step 1: Recall the Maclaurin series for eue^u

The Maclaurin series is a special case of the Taylor series where the expansion is centered at x=0x = 0. We know the Maclaurin series for eue^u is given by the sum from n=0n=0 to infinity of unu^n divided by n!n!. This series converges for all real values of uu.

Step 2: Substitute u=x2u = x^2 into the series

To find the Taylor series for f(x)=ex2f(x) = e^{x^2} centered at x=0x = 0, we substitute u=x2u = x^2 into the Maclaurin series for eue^u. This gives us the series in terms of xx.

Step 3: Write out the first few terms of the series

Expanding the series, we can write out the first few terms to better visualize the pattern. This gives us 1+x2+x42!+x63!+…1 + x^2 + \frac{x^4}{2!} + \frac{x^6}{3!} + \dots.

Step 4: Determine the interval of convergence

We use the Ratio Test to find the interval of convergence. Let an=x2nn!a_n = \frac{x^{2n}}{n!}. We calculate the limit of the absolute value of the ratio of consecutive terms, an+1an\frac{a_{n+1}}{a_n}. Since the limit is 00, which is less than 11, the series converges for all real values of xx.

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