式1: "f" left parenthesis, "x" , right parenthesis equals 1 third "x" cubed minus 2 "x" squared plus 3 "x"fx=13x3−2x2+3x
1
式2: "f" prime left parenthesis, 1 , right parenthesis left parenthesis, "x" minus 1 , right parenthesis plus "f" left parenthesis, 1 , right parenthesisf′1x−1+f1