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\(\cfrac{x}{xa+yb+zc}=\cfrac{y}{ya+zb+xc} =\cfrac{z}{za+xb+yc} \)
\(= \cfrac{x+y+z}{xa+yb+zc+ya+zb+xc+za+xb+yc}\) [সং যোজন প্রক্রিয়া করে পাই]
\(=\cfrac{x+y+z}{x(a+b+c)+y(a+b+c)+z(a+b+c)}\)
\(=\cfrac{x+y+z}{(a+b+c)(x+y+z)}\)
\(=\cfrac{1}{a+b+c}\)

\(\therefore \cfrac{x}{xa+yb+zc}=\cfrac{y}{ya+zb+xc} =\cfrac{z}{za+xb+yc} =\cfrac{1}{a+b+c}\) (প্রমানিত)