- #36
Birchyuk
- 8
- 0
Good evening,
I am also struggling on this question and have been for a solid week.
I am currently trying to calculate an. I so far have:
I have assumed for the time being x=wt
[itex] \int sinxcosnx.dx [/itex]
[itex] \frac{1}{2} \int sin(n+1)x+sin(n-1)x.dx [/itex]
[itex] \frac {1}{2} (\frac {-cos(n+1)x} {n+1} + (\frac {-cos(n-1)x}{n-1}) [/itex]
I have input the limits of x between [itex] pi [/itex] and [itex] \frac {pi}{2} [/itex] and subtracted there. Furthermore i have done the same to [itex] 2pi [/itex] and [itex] \frac {3pi}{2} [/itex] and added these but my result continually comes out at 0. I am expecting only odd numbers of n will produce a result. I have tried a few methods but none of them seem to be working.My hunch is that I am not integrating correctly or I am misunderstanding the relevance of (wt)?
Any assistance would be appreciate greatly.
I am also struggling on this question and have been for a solid week.
I am currently trying to calculate an. I so far have:
I have assumed for the time being x=wt
[itex] \int sinxcosnx.dx [/itex]
[itex] \frac{1}{2} \int sin(n+1)x+sin(n-1)x.dx [/itex]
[itex] \frac {1}{2} (\frac {-cos(n+1)x} {n+1} + (\frac {-cos(n-1)x}{n-1}) [/itex]
I have input the limits of x between [itex] pi [/itex] and [itex] \frac {pi}{2} [/itex] and subtracted there. Furthermore i have done the same to [itex] 2pi [/itex] and [itex] \frac {3pi}{2} [/itex] and added these but my result continually comes out at 0. I am expecting only odd numbers of n will produce a result. I have tried a few methods but none of them seem to be working.My hunch is that I am not integrating correctly or I am misunderstanding the relevance of (wt)?
Any assistance would be appreciate greatly.