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FP3 Reduction formulae

This question is kinda annoying. I've managed to do both (a) and (b), but stuck on (c).


Any ideas on how to approach this?
Reply 1
Original post by P____P
This question is kinda annoying. I've managed to do both (a) and (b), but stuck on (c).


Any ideas on how to approach this?


Why not just use part a) to show they're all the same, and then I guess part b) for the second part.
(edited 8 years ago)
Reply 2
Original post by joostan
Why not just use part a)?



Yh that was my initial line of thought (on the pdf). But stuck after that point.:redface:
Reply 3
Original post by P____P
Yh that was my initial line of thought (on the pdf). But stuck after that point.:redface:


Looks good to me, what seems to be the problem?
Reply 4
Original post by joostan
Looks good to me, what seems to be the problem?


The problem seems to be that I am supposed to get a value and I have a function?
Reply 5
Original post by P____P
The problem seems to be that I am supposed to get a value and I have a function?


Sorry, the line above that with the question mark is correct, and of course sin(nπ)=0\sin(n \pi)=0.
Reply 6
Original post by joostan
Sorry, the line above that with the question mark is correct, and of course sin(nπ)=0\sin(n \pi)=0.


So, that means that the first integral is equivalent to the second integral, but how do I simplify that?
Reply 7
Original post by P____P
So, that means that the first integral is equivalent to the second integral, but how do I simplify that?


Well you know for each nN, InIn1=0n \in \mathbb{N} , \ I_n-I_{n-1}=0 which surely implies the result. . .
(edited 8 years ago)
Reply 8
Original post by P____P
This question is kinda annoying. I've managed to do both (a) and (b), but stuck on (c).


Any ideas on how to approach this?


This means In=In1=In2==I0=0π/2sinxsinxdx\displaystyle I_n = I_{n-1} = I_{n-2} = \cdots = I_{0} = \int_0^{\pi/2} \frac{\sin x}{\sin x} \, \mathrm{d}x - you can easily do the integral.
Reply 9
Original post by joostan
Well you know for each nN, InIn1=0n \in \mathbb{N} , \ I_n-I_{n-1}=0 which surely implies the result. . .


Original post by Zacken
This means In=In1=In2==I0=0π/2sinxsinxdx\displaystyle I_n = I_{n-1} = I_{n-2} = \cdots = I_{0} = \int_0^{\pi/2} \frac{\sin x}{\sin x} \, \mathrm{d}x - you can easily do the integral.


Thanks for the help.

Much appreciated:smile:

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