FindRoot and NIntegrate

*To*: mathgroup at smc.vnet.net*Subject*: [mg81850] FindRoot and NIntegrate*From*: mfedert at gmail.com*Date*: Fri, 5 Oct 2007 04:44:01 -0400 (EDT)

Hi all, I have what is probably a very simple problem. I want to find x which solves an equation of the form \integral f(x,y) dy = 0 I have tried something along the lines of FindRoot[ NIntegrate[ f(x,y) , {y, -inf, inf} ], {x, x_0 } ] but it doesn't work ---- my theory being that NIntegrate tries to go ahead and do the numerical integration before it knows what x is equal to... which blows up because the integrand is - as a function of x - non-numerical... Is there a way around this? I'm sure there's some trivial modification I can make to get things working again. Thanks, in anticipation --- MF