How to normalize curves such that area under curve=1?

I'm trying to plot three curves such that area under curve =1. I've tried trapz but it only gives me the area and i couldn't change it.

Any idea?

Answer 1

[Mohammad Abouali]

divide all numbers by the area that you calculate using Trapz.

x=0:0.1:pi;
y=sin(x);
Area=trapz(x,y)

Area =

      1.9975

y_normalized=y./Area;
trapz(x, y_normalized)

ans =

      1.0000

[Image Analyst]

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