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Integral calculation on a curve in Excel

chimistehw -  
 TZ -
Hello,

I plotted a graph y=f(x) and I am trying to calculate the integral of the trendline between x=0 and x=xmax (for y=0). I am using Excel 2007 and I can't find the appropriate formula.
Thank you in advance.

2 answers

  1.
    Raymond PENTIER Posted messages 58210 Registration date   Status Contributor Last intervention   17 480
     
    Hello.
    Such a formula does not exist.
    Reminder of the definition: "If f is a positive continuous real function taking its values in a segment I = [0,a], then the integral of f over I is the area of a surface bounded by the graph of ƒ and by the three lines with equations x=0, x=a, y=0"
    Calculating the integral of a function between 2 values amounts to performing a numerical analysis, that is to say calculating a succession of areas, using the rectangle method or the trapezoid method, among other processes. It is then possible to automate these operations on a spreadsheet.

    http://en.wikipedia.org/wiki/Integration_(mathematics)
    https://en.wikipedia.org/wiki/Numerical_integration

    You can also do it like in high school: plot the graph with a very fine grid and count the squares to estimate the area of the figure.
    --
    Retirement is great! Especially in the Caribbean... :-)
    ☻ Raymond ♂
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