Expression 1: Start sum from "n" equals 1 to "x" , end sum, "n" times 1 half left parenthesis, StartFraction, StartAbsoluteValue, mod left parenthesis, floor left parenthesis, "x" , right parenthesis , "n" , right parenthesis plus 0.5 , EndAbsoluteValue Over mod left parenthesis, floor left parenthesis, "x" , right parenthesis , "n" , right parenthesis plus 0.5 , EndFraction minus StartFraction, StartAbsoluteValue, mod left parenthesis, floor left parenthesis, "x" , right parenthesis , "n" , right parenthesis minus 0.5 , EndAbsoluteValue Over mod left parenthesis, floor left parenthesis, "x" , right parenthesis , "n" , right parenthesis minus 0.5 , EndFraction , right parenthesisx∑n=1n·12modfloorx,n+0.5modfloorx,n+0.5−modfloorx,n−0.5modfloorx,n−0.5