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 Apr16 awarded Necromancer Apr12 comment maximal ideal of a polynomial ring They are ideals, indeed. Just not maximal. Do you see why? Mar28 awarded Nice Question Mar15 answered Passing from basis of topology to regular definition of open sets Mar10 awarded Nice Question Mar3 accepted How to solve $tx'(t) = (2t^2 + 1)x(t) + t^2$? Mar3 comment How to solve $tx'(t) = (2t^2 + 1)x(t) + t^2$? Yes that's what I meant when saying $c = \sqrt(\pi)/2$. Still am clueless on how to proceed, I must shamefully admit.. Thanks for your help in any case! :) Feb26 accepted Find the limit of $x_n = \sin(2\pi (n^3 − n^2 + 1)^{1/3} )$ Feb26 asked Find the limit of $x_n = \sin(2\pi (n^3 − n^2 + 1)^{1/3} )$ Feb26 comment How to solve $tx'(t) = (2t^2 + 1)x(t) + t^2$? with a lot of work I was able to show the limit is bounded from above by 1/2 (or -1/2, I lost track of the sign). Since the function we're taking the limit of is increasing, this shows the limit exists.. But I am using $t \cdot \int_{t}^{t+k} e^{-x^2}dx < \int_{t}^{t+k} t \cdot e^{-x^2}dx$ and I cannot see any other way to do it without this strict inequality.. Could you give another hint on how to proceed? Feb26 comment How to solve $tx'(t) = (2t^2 + 1)x(t) + t^2$? Whoops I meant $-\sqrt(\pi)/2$ of course.. Feb26 comment How to solve $tx'(t) = (2t^2 + 1)x(t) + t^2$? Yes I guess $c$ should be $\sqrt(\pi)/2$ if we set $t_0 = 0$. I am trying out different approaches now to calculate this limit, but without success so far.. Feb26 comment How to solve $tx'(t) = (2t^2 + 1)x(t) + t^2$? @Amzoti I just learned about the integrating factor, thanks for the reference! Is the thing I stumbled upon what you meant with "something seems wrong"? Feb26 revised How to solve $tx'(t) = (2t^2 + 1)x(t) + t^2$? added 630 characters in body Feb26 comment How to solve $tx'(t) = (2t^2 + 1)x(t) + t^2$? @Amzoti , yes I just rechecked. It is question number 10 from mathematics.ceu.edu/sites/mathematics.ceu.hu/files/attachment/… if you want to take a look. Feb26 asked How to solve $tx'(t) = (2t^2 + 1)x(t) + t^2$? Feb26 comment Integration of $\int_{-\infty}^{\infty} e^{-x^2 + 2x} dx$ Thanks for the answer Tim. The other addressed my question slightly more directly, so I accepted that one. Nevertheless your one was useful as well! Feb26 comment Integration of $\int_{-\infty}^{\infty} e^{-x^2 + 2x} dx$ That is great @kobe, I will check it out. Feb26 comment Integration of $\int_{-\infty}^{\infty} e^{-x^2 + 2x} dx$ Hi Kobe, could you state the other ways from the "number of ways"? I'll check them out via google. Thanks! Feb26 accepted Integration of $\int_{-\infty}^{\infty} e^{-x^2 + 2x} dx$