Business School, Sichuan University
Homework 9 (100 points)
Course Name：Business Calculus-II
Lecturer: Ziqiang Zeng
Student Name：Ehab hazaea Ali Hassan Student ID:2018521080431
Score:
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1.
Answer q1
Major:IBM
2.
Answer:
With right endpoints: -6.4
With left endpoints: 3.8
With midpoints: -1
Step-by-step explanation:
Given
x
3
4
5
6
7
8
9
f(x) −3.4 −2.2 −0.6 0.2 0.8 1.5 1.7
We are asked to estimate the integral 3 to 9 f(x) dx.
Using the intervals 3 to 5, 5 to 7 and 7 to 9, the length of the intervals
is Δx = 2
With right endpoints the integral is:
f(3)*Δx + f(5)*Δx + f(7)*Δx = (-3.4)*2 + (-0.6)*2 + 0.8*2 = -6.4
With left endpoints the integral is:
f(5)*Δx + f(7)*Δx + f(9)*Δx = (-0.6)*2 + 0.8*2 + 1.7*2 = 3.8
With midpoint s the integral is:
f(4)*Δx + f(6)*Δx + f(8)*Δx = (-2.2)*2 + 0.2*2 + 1.5*2 = -1
3.
Answer 9
9:the approximate ingtegral = -20.4
10:
4.
5.
6.