表达式1: "S" left parenthesis, "x" , right parenthesis equals 3 "x" squared minus 2 "x" cubedSx=3x2−2x3
1
表达式2: "S" left parenthesis, "S" left parenthesis, "S" left parenthesis, "S" left parenthesis, "S" left parenthesis, "S" left parenthesis, "S" left parenthesis, "S" left parenthesis, "S" left parenthesis, "x" , right parenthesis , right parenthesis , right parenthesis , right parenthesis , right parenthesis , right parenthesis , right parenthesis , right parenthesis , right parenthesisSSSSSSSSSx