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**trojsi** Hi,

in a question of my assignment i was asked to find the integral of $\displaystyle e^{-x/2}cos(2x)$ which I found it to be $\displaystyle \frac{e^{-x/2}(8sin(2x)-2cos(2x))}{17}$ with Integration by parts that had to be done 2 times and finally with the reduction method. In the last part of the question he asks: "hence find the rms value of $\displaystyle e^{-x/4}sinx$. I noticed that this was already tackled in a step of the previous integration but I am not sure on the rms part. I am aware that the rms is the equivalent area. (equivalent D.C component) Can you please give me a hint or maybe post some good links to where I can understand the relation between rms and integration ?