Recent content by chener

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    Undergrad Calculate the standard deviation of Gaussian distribution ,thanks

    Given a one-dimensional Gaussian distribution, distributed as following: f (x) = exp (-x ^ 2 / (2q)) / q / √ (2pi) proof which q is the standard deviation Thanks !The standard deviation is defined by: http://www.mathsisfun.com/data/standard-deviation-formulas.html
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    Graduate Can you prove a differential equation has no analytical solution?

    Yes ,this is my mean! thanks!
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    Graduate Can you prove a differential equation has no analytical solution?

    Given a Differential Equation. Is there Analytic Solutions or not? And how do we know that?example: Given the equation y''=-y-y'+(1+|y|)*sin(t) ,how to prove a it has no analytical solution?Teach me ,please! Thank you a lot! Analytic Solution is resovle from Analytic Method.
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    Graduate Can you prove a differential equation has no analytical solution?

    Sorry my English is poor ! Let me think about how to express
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    Graduate Can you prove a differential equation has no analytical solution?

    Can you prove a differential equation has no analytical solution? Teach me ,please! Thank you a lot!