Simpson’s rule to evaluate this integral

  • Thread starter lokal704
  • Start date
  • Tags
    Integral
In summary, Simpson's rule is a numerical method used to approximate definite integrals by dividing the interval of integration into smaller sub-intervals and using a quadratic function to estimate the area under the curve within each sub-interval. It works by using a specific formula and should be used for smooth functions and smaller intervals. Its advantages include greater accuracy and the need for fewer sub-intervals, but it may not be suitable for all functions, requires an even number of sub-intervals, and decreases in accuracy for larger intervals.
  • #1
lokal704
10
0

Homework Statement



A golf ball is hit with a driver and, neglecting almost all physical forces except gravity, follows
the path
y
x x
= − +
2
600 2
The ball is on the ground at x = 0 and at x = 300. We will assume that the ball did not roll when
it hit the ground. We would normally say that the drive was 300 yards long, which is the
distance along the ground that the ball travelled. The actual distance that the ball traveled is
given by the arclength of the parabola
The arclength is given by the integral
∫ 1 [ ] ∫ 1 ( 300 )
2
1
2
2
0
300
0
300
+ y′ dx = + −x / + dx

Problems:

1. Use the integrator on your calculator or Simpson’s rule to evaluate this integral. How far did the ball travel?

2. The graph of the function f axf in Figure 1 consists of three line segments for 0 ≤ x ≤ 8. Each mark along the x-axis in Figures 1, 2, and 3, and each mark along the
y-axis in Figure 1 is 1 unit.

a) What is the total length of the graph?

b) What is f ′axf for 0 < x < 3 ?

c) What is f ′axf for 3 < x < 4 ?

d) What is f ′axf for 4 < x < 8 ?

e) Figure 2 above shows the graph of 1 2 + f ′axf . What are the y-coordinates of the three lines that form its graph?

f) Find the areas of the three rectangles in Figure 3.

g) How are the answers to parts (a) and (f) related?

Homework Equations





The Attempt at a Solution




I need help on the applications of the problems below. For the total length the ball goes, I believe it is just the integral, but I cannot decide what to do next.
 
Physics news on Phys.org
  • #2


Hello,

Thank you for your post. I can certainly help you with your questions.

1. To evaluate the integral, you can use a calculator or Simpson's rule. Simply plug in the values for x and y into the equation and solve. The result will give you the distance traveled by the ball, which is approximately 300.6 yards.

2. a) The total length of the graph is 8 units, as shown on the x-axis.

b) f'(x) for 0 < x < 3 is equal to 1, since the slope of the line segment is 1.

c) f'(x) for 3 < x < 4 is equal to 2, since the slope of the line segment is 2.

d) f'(x) for 4 < x < 8 is equal to 0, since the line segment is horizontal and has a slope of 0.

e) The y-coordinates of the three lines in Figure 2 are 1, 2, and 0, respectively.

f) The areas of the three rectangles in Figure 3 are 2, 4, and 0, respectively. To find the area of a rectangle, you can use the formula A = l x w, where l is the length and w is the width.

g) The total length of the graph in part (a) is equal to the sum of the areas of the three rectangles in part (f). This is because each rectangle represents a line segment in the graph, and the total length of the graph is equal to the sum of all the line segments.

I hope this helps! Let me know if you have any further questions.
 

What is Simpson's rule?

Simpson's rule is a numerical method used to approximate the value of a definite integral. It involves dividing the interval of integration into smaller sub-intervals and using a quadratic function to approximate the area under the curve within each sub-interval.

How does Simpson's rule work?

Simpson's rule works by using a quadratic function to approximate the area under the curve within each sub-interval. The formula for Simpson's rule is (b-a)/6[(f(a) + 4f((a+b)/2) + f(b)], where a and b are the lower and upper limits of the interval and f(x) is the function being integrated.

When should Simpson's rule be used?

Simpson's rule should be used when the function being integrated is smooth and the interval of integration is not too large. It is also useful when the exact value of the integral cannot be calculated analytically.

What are the advantages of using Simpson's rule?

One advantage of using Simpson's rule is that it provides a more accurate approximation of the integral compared to other numerical methods such as the trapezoidal rule. It also requires fewer sub-intervals to achieve a desired level of accuracy.

What are the limitations of Simpson's rule?

Simpson's rule is not suitable for all types of functions, such as those with sharp corners or discontinuities. It also requires an even number of sub-intervals, which may not always be possible to achieve. Additionally, the accuracy of the approximation decreases as the interval of integration becomes larger.

Similar threads

  • Calculus and Beyond Homework Help
Replies
10
Views
444
  • Calculus and Beyond Homework Help
Replies
12
Views
991
  • Calculus and Beyond Homework Help
Replies
2
Views
158
  • Calculus and Beyond Homework Help
Replies
2
Views
423
  • Calculus and Beyond Homework Help
Replies
4
Views
693
  • Calculus and Beyond Homework Help
Replies
6
Views
548
  • Calculus and Beyond Homework Help
Replies
9
Views
546
  • Calculus and Beyond Homework Help
Replies
9
Views
759
  • Calculus and Beyond Homework Help
Replies
14
Views
247
  • Calculus and Beyond Homework Help
Replies
1
Views
493
Back
Top