색칠된 부분은 기체가 한 일이다. 녹색은 기체가 일을 한 경우이고, 적색은 기체가 일을 받은 경우이다. 구간별로 색깔을 표시해서 학생들의 이해를 돕는다.
47
Expression 48: 0 less than "y" less than "f" left parenthesis, "x" , right parenthesis left brace, left parenthesis, "x" Subscript, 1 , Baseline minus "x" , right parenthesis left parenthesis, "x" Subscript, 2 , Baseline minus "x" , right parenthesis less than 0 , right brace0<y<fxx1−xx2−x<0
48
Expression 49: "U" equals Start integral from "x" Subscript, 1 , Baseline to "x" Subscript, 2 , Baseline , end integral, "f" left parenthesis, "x" , right parenthesis "d" "x"U=∫x2x1fxdx
equals=
23.7 9 1 1 6 2 1 5 6 423.7911621564
49
Expression 50: 0 less than "y" less than "g" left parenthesis, "x" , right parenthesis left brace, left parenthesis, "x" Subscript, 1 , Baseline minus "x" , right parenthesis left parenthesis, "x" Subscript, 2 , Baseline minus "x" , right parenthesis less than 0 , right brace0<y<gxx1−xx2−x<0
50
Expression 51: "D" equals Start integral from "x" Subscript, 1 , Baseline to "x" Subscript, 2 , Baseline , end integral, "g" left parenthesis, "x" , right parenthesis "d" "x"D=∫x2x1gxdx
equals=
14.2 7 4 6 9 7 2 9 3 814.2746972938
51
Expression 52: "k" equals StartFraction, "U" Over "D" , EndFractionk=UD