choice of method: set c=0 for left-hand sum, c=1 for right-hand sum, c=0.5 for midpoint sum
9
表达式10: "c" equals 0c=0
negative 10−10
1010
10
Integral approximation
11
表达式12: "I" equals Start sum from "i" equals 0 to "n" negative 1, end sum, "f" left parenthesis, "s" left parenthesis, "i" , right parenthesis , right parenthesis times "w"I=n−1∑i=0fsi·w