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bobred
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Homework Statement
Show that
[tex]\sum_{r=0}^\infty\frac{1}{(2r+1)^2}=\frac{\pi^2}{8}[/tex]
Homework Equations
The equation of the function is
[tex]F(t)&=&\dfrac{\pi}{4}-\dfrac{2}{\pi}\left(\cos t+\dfrac{\cos3t}{3^{2}}+\dfrac{\cos5t}{5^{2}}+\cdots\right)-\left(\sin t-\dfrac{\sin2t}{2}+\dfrac{\sin3t}{3}-\cdots\right)[/tex]
The Attempt at a Solution
We are given the condition that t=0, so the cos terms are all 1 giving
[tex]\left(\cos t+\dfrac{\cos3t}{3^{2}}+\dfrac{\cos5t}{5^{2}}+\cdots\right)=\dfrac{1}{1^{2}}+\dfrac{1}{3^{2}}+\dfrac{1}{5^{2}}+\dfrac{1}{7^{2}}\cdots=\frac{\pi^2}{8}[/tex]
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