Maxima of sum of two gaussians











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I am trying to find an analytical form of the maxima of the function



$$f(x) = a_1 e^{-b^2_1 x^2} + a_2 e^{-b^2_2 (x+x_c)^2} , tag{1}$$



such that I can define a function $g(x)$ that has the maximum value $max (g(x)) = 1$, i.e.



$$g(x):= frac{f(x)}{max (f(x))} $$



The parameter $x_c$ is such that the maxima is unique or in other words only one maxima exists. For example, take the case where $x_c = 0.017,b^2_1=10,b^2_2=3,a_1=0.8,a_2=0.2$. The function $f(x)$ has only a single maxima with these parameters.



I could only come up with an approximate solution where $max(g(x)) approx 1$, i.e.



$$g(x):= frac{f(x)}{a_1 + a_2 e^{-b^2_2 (x_c)^2}} $$



Is there an exact solution to my problem?.










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    up vote
    2
    down vote

    favorite












    I am trying to find an analytical form of the maxima of the function



    $$f(x) = a_1 e^{-b^2_1 x^2} + a_2 e^{-b^2_2 (x+x_c)^2} , tag{1}$$



    such that I can define a function $g(x)$ that has the maximum value $max (g(x)) = 1$, i.e.



    $$g(x):= frac{f(x)}{max (f(x))} $$



    The parameter $x_c$ is such that the maxima is unique or in other words only one maxima exists. For example, take the case where $x_c = 0.017,b^2_1=10,b^2_2=3,a_1=0.8,a_2=0.2$. The function $f(x)$ has only a single maxima with these parameters.



    I could only come up with an approximate solution where $max(g(x)) approx 1$, i.e.



    $$g(x):= frac{f(x)}{a_1 + a_2 e^{-b^2_2 (x_c)^2}} $$



    Is there an exact solution to my problem?.










    share|cite|improve this question
























      up vote
      2
      down vote

      favorite









      up vote
      2
      down vote

      favorite











      I am trying to find an analytical form of the maxima of the function



      $$f(x) = a_1 e^{-b^2_1 x^2} + a_2 e^{-b^2_2 (x+x_c)^2} , tag{1}$$



      such that I can define a function $g(x)$ that has the maximum value $max (g(x)) = 1$, i.e.



      $$g(x):= frac{f(x)}{max (f(x))} $$



      The parameter $x_c$ is such that the maxima is unique or in other words only one maxima exists. For example, take the case where $x_c = 0.017,b^2_1=10,b^2_2=3,a_1=0.8,a_2=0.2$. The function $f(x)$ has only a single maxima with these parameters.



      I could only come up with an approximate solution where $max(g(x)) approx 1$, i.e.



      $$g(x):= frac{f(x)}{a_1 + a_2 e^{-b^2_2 (x_c)^2}} $$



      Is there an exact solution to my problem?.










      share|cite|improve this question













      I am trying to find an analytical form of the maxima of the function



      $$f(x) = a_1 e^{-b^2_1 x^2} + a_2 e^{-b^2_2 (x+x_c)^2} , tag{1}$$



      such that I can define a function $g(x)$ that has the maximum value $max (g(x)) = 1$, i.e.



      $$g(x):= frac{f(x)}{max (f(x))} $$



      The parameter $x_c$ is such that the maxima is unique or in other words only one maxima exists. For example, take the case where $x_c = 0.017,b^2_1=10,b^2_2=3,a_1=0.8,a_2=0.2$. The function $f(x)$ has only a single maxima with these parameters.



      I could only come up with an approximate solution where $max(g(x)) approx 1$, i.e.



      $$g(x):= frac{f(x)}{a_1 + a_2 e^{-b^2_2 (x_c)^2}} $$



      Is there an exact solution to my problem?.







      calculus real-analysis optimization






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      asked Nov 15 at 23:16









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