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joris_pixie
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I'm particle physics at the moment and I don't get why the average value of cosˆ2 is 1/3.
The section :
My solution is :
[tex]< cos^{2}(\alpha)> = \frac{1}{\pi - 0} \int_{0}^{\pi } cos^{2}(\alpha)sin(\alpha)d\alpha[/tex]
I substitute
[tex]u = cos(\alpha)[/tex]
so i get
[tex]-\frac{1}{\pi}\int_{1}^{-1}u^{2}du = \frac{2}{3\pi}[/tex]
What I am i doing wrong ? :(
I'm particle physics at the moment and I don't get why the average value of cosˆ2 is 1/3.
The section :
My solution is :
[tex]< cos^{2}(\alpha)> = \frac{1}{\pi - 0} \int_{0}^{\pi } cos^{2}(\alpha)sin(\alpha)d\alpha[/tex]
I substitute
[tex]u = cos(\alpha)[/tex]
so i get
[tex]-\frac{1}{\pi}\int_{1}^{-1}u^{2}du = \frac{2}{3\pi}[/tex]
What I am i doing wrong ? :(
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