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Verify an exponential–sine series by two methods

For y=exsin⁡xy=e^x\sin x, show y′′=2(y′−y)y^{\prime\prime}=2(y^{\prime}-y). Differentiate this further to find the Maclaurin series through x3x^3, then verify it using the standard series for exe^x and sin⁡x\sin x. marks

[2008/CJC/Promo/11]

CJC · Review problems · Question 5

Use the recurrence to obtain derivatives at zero, then check the same coefficients by multiplication.

Read the worked solution