1. The problem statement, all variables and given/known data Here's a screenshot of the problem: http://puu.sh/2Bta5 [Broken] 2. Relevant equations 3. The attempt at a solution As can be seen by the screenshot, the answer's already given, but I'm not sure how to go about getting it. This one has me stumped since e-4x and sin(5x) are both Maclaurin series that I can easily find. But I'm not sure where to go from there, or if I'm even supposed to use both of the Maclaurin series.