Thursday 27 February 2014

Problem of the week

Find the general solution of this ODE \[ x^{2}\frac{d^{2}y}{dx^{2}}-x\frac{dy}{dx}+y=x \] To find \[ \sum_{k=2}^{\infty}\dfrac{1}{k^{2}-1} \] We use this identity given from partial fractions $\dfrac{1}{k^{2}-1}\equiv\dfrac{\frac{1}{2}}{k-1}-\dfrac{\frac{1}{2}}{k+1}$
Then we use method of differences...try it