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 Jan16 comment How to calculate the approximate zero of any polynomial function without Newton's Method? @Xoque55 Newton's method can work for $x^2+1=0$ if your starting point has a nonzero imaginary part. Jan8 awarded Famous Question Jan4 awarded Popular Question Dec17 answered What are some applications of elementary linear algebra outside of math? Oct29 accepted How to fill in these steps to evaluate this Gaussian integral? Sep23 comment Really advanced techniques of integration (definite or indefinite) +1 Risch's algorithm has a 100 page summary. Talk about an advanced technique. Sep4 accepted Transforming a nonlinear system to a linear system Sep4 comment Transforming a nonlinear system to a linear system It is part of a much larger nonlinear regression problem. But this can also stand alone on its own. I have three points and I want to determine $a$, $b$, and $c$ so that the Lorentzian curve goes through those three points. If I solve the nonlinear system, I need iterative methods and a starting value. I am trying to see if I can transform it into a linear system and then use a direct linear solver without an initial value. Sep4 comment Transforming a nonlinear system to a linear system Not quite what I was looking for. I don't want to solve the 3x3 system using exact arithmetic. I want to change the nonlinear system to a linear 3x3 system so that I can use a numerically stable direct linear solver. This method is unstable if any of the $y_i$'s are too close or too far apart. +1 for solving the Lorentzian system though. Thanks. Sep4 asked Transforming a nonlinear system to a linear system Aug30 reviewed Close Linear Transformation $T-T^2=I$ Aug30 reviewed Close Caratheodory: Motivation Jul16 comment How to fill in these steps to evaluate this Gaussian integral? Cool, thanks. I'll keep playing with this and see if I can use this to get the general case. Jul13 revised How to fill in these steps to evaluate this Gaussian integral? added 276 characters in body Jul13 comment How to fill in these steps to evaluate this Gaussian integral? I know for $\mu=0$, the sum is zero. But how can we get the expression even for $\mu=0$? Jul13 asked How to fill in these steps to evaluate this Gaussian integral? Jul2 awarded Curious Jul2 comment Units of a log of a physical quantity You reasoning is flawed. Different units can be multiplied/divided but they cannot be added/subtracted. For example, you can divide meters by seconds and get meters per seconds but you cannot add seconds+meters. That is why taking the log of a unit doesn't make sense because log(1+x) = x-x^2/2+x^3/3... So how can you add sec-sec^2+sec^3...? Jun12 reviewed Approve Can a coin with an unknown bias be treated as fair? May12 answered College Math Competitions