Expression 3: "F" Subscript, "a" "p" "p" "r" "o" "x" "i" "m" "a" "t" "i" "o" "n" , Baseline left parenthesis, "x" , right parenthesis equals Start sum from "n" equals 1 to "P" Subscript, "p" "r" "e" "c" "i" "s" "i" "o" "n" , Baseline , end sum, StartFraction, "y" Subscript, 1 , Baseline left bracket, "n" , right bracket Over left parenthesis, "n" minus 1 , right parenthesis ! , EndFraction StartFraction, left parenthesis, "x" minus "a" , right parenthesis Superscript, "n" , Baseline Over "n" , EndFractionFapproximationx=Pprecision∑n=1y1nn−1!x−ann
