Expression 7: "y" minus "g" left parenthesis, "c" , right parenthesis equals "g" prime left parenthesis, "c" , right parenthesis left parenthesis, "x" minus "c" , right parenthesis left brace, "c" minus StartFraction, pi Over 2 , EndFraction less than or equal to "x" less than or equal to "c" plus StartFraction, pi Over 2 , EndFraction , right bracey−gc=g′cx−cc−π2≤x≤c+π2
Expression 9: "y" equals "g" prime left parenthesis, "x" , right parenthesis left brace, negative 2 pi less than or equal to "x" less than or equal to "c" , right bracey=g′x−2π≤x≤c