What will be the pdf of $X+Y$?












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Suppose $X$ and $Y$ are independent random variables. Let $f$ and $g$ be the pdf of $X$ and $Y$ respectively. Let $h$ be the pdf of $X+Y$ then can we say that $h(x)=f(x)g(x),$ for all $x in Bbb R$? If so why?



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    Suppose $X$ and $Y$ are independent random variables. Let $f$ and $g$ be the pdf of $X$ and $Y$ respectively. Let $h$ be the pdf of $X+Y$ then can we say that $h(x)=f(x)g(x),$ for all $x in Bbb R$? If so why?



    Please help me in this regard. Thank you very much.










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      Suppose $X$ and $Y$ are independent random variables. Let $f$ and $g$ be the pdf of $X$ and $Y$ respectively. Let $h$ be the pdf of $X+Y$ then can we say that $h(x)=f(x)g(x),$ for all $x in Bbb R$? If so why?



      Please help me in this regard. Thank you very much.










      share|cite|improve this question













      Suppose $X$ and $Y$ are independent random variables. Let $f$ and $g$ be the pdf of $X$ and $Y$ respectively. Let $h$ be the pdf of $X+Y$ then can we say that $h(x)=f(x)g(x),$ for all $x in Bbb R$? If so why?



      Please help me in this regard. Thank you very much.







      probability probability-theory random-variables independence density-function






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      asked Nov 30 '18 at 18:40









      Dbchatto67Dbchatto67

      52215




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          It is called convolution



          $h(x) = int_{-infty} ^ {infty} f(y) g(x-y) dy $






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            1 Answer
            1






            active

            oldest

            votes








            1 Answer
            1






            active

            oldest

            votes









            active

            oldest

            votes






            active

            oldest

            votes









            4














            It is called convolution



            $h(x) = int_{-infty} ^ {infty} f(y) g(x-y) dy $






            share|cite|improve this answer


























              4














              It is called convolution



              $h(x) = int_{-infty} ^ {infty} f(y) g(x-y) dy $






              share|cite|improve this answer
























                4












                4








                4






                It is called convolution



                $h(x) = int_{-infty} ^ {infty} f(y) g(x-y) dy $






                share|cite|improve this answer












                It is called convolution



                $h(x) = int_{-infty} ^ {infty} f(y) g(x-y) dy $







                share|cite|improve this answer












                share|cite|improve this answer



                share|cite|improve this answer










                answered Nov 30 '18 at 18:46









                MoonKnightMoonKnight

                1,324611




                1,324611






























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