silemus.

43Maclaurin series of e2xe^{2x}

Find the coefficient of x3\displaystyle x^3 in the Maclaurin series of e2x\displaystyle e^{2x}. Give the answer to 3 decimal places.

Substitute u = 2x into the series for e^u, then pick the n = 3 term: (2x)³/3! = 8x³/6. So the coefficient of x³ is 4/3 ≈ 1.333.

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