Integrability of Sinusoidal Function on [-1, 1]: Finding L(f, P) and U(f, P)

neom
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The problem states:

Decide if the following function is integrable on [-1, 1]

f(x)=\left\{{sin(\frac1{x^2})\;\text{if}\;x\in[-1,\;0)\cup(0,\;1]\atop a\;\text{if}\;x=0}

where a is the grade, from 1 to 10, you want to give the lecturer in this course

What I don't understand is how to find L(f, P) and U(f, P) since when I look at the graph of the function it oscillates a lot. So how do I choose the partition. It seems I would need an infinite partition almost to make it work. Or is there another way to do it?

Any help would be much appreciated as I am really lost on this problem.'

Edit: Sorry for the function not showing properly, don't know what I did wrong there

Should be

sin(\frac1{x^2})\;\text{if}\;x\in[-1,\;0)\cup(0,\;1]
&
a\;\text{if}\;x=0
 
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Showing something is Riemann integrable doesn't mean you have to choose partitions. You probably have some theorems that you can use to show f(x) is Riemann integrable outside of any interval [-\epsilon,\epsilon]. Now show you can choose upper and lower partitions inside that interval that approach 0 as ε approaches 0.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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