تم الحل ✓
categoryرياضيات
schoolبكالوريوس
event_available2026-07-13
السؤال
Transcribed Image Text:
Honors
BC.ch14.projects.pdf
Guided Project 69: How big are n-balls?
Topics and skills: Multiple integration
We generally think of a ball as a three-dimensional sphere and the points inside of it. However, a bull may be
defined in any number of dimensions and balls in n-dimensions are called balls, for 21. For example.
⚫the 1-ball of radius is the interval Bond Sr]
⚫ the 2-ball of radius is the disk Bar) x y
⚫the 3-ball of radius is the "common ball Bix+y+S+)
⚫ in general, the n-ball of radius is the se
Notice that for 1, 2, and 3, the sizes (or solmes) of the balls are V2
and
Vir) 4'3. In this project we show how to compute the volume of balls with a>3. We reach the
remarkable conclusion that the volumes of unit balls (those with
1. Let's review the computation of the volume of the 3-bull of radius r. Working in Cartesian coordinates
(even though the computation is easier in spherical coordinates, explain why
(The factor of 8 arises because of symmetry)
2. Use a trigonometric substitution to evaluate the integral in Step 1 and confirm that
43
3. Here is a different way to view the calculation of Vin that allows us to move to higher dimensions. We
write the integral in Step 1 as
-
Explain why the inner two integrals equal (√). 14 of the volume of a 2 bull of radius
4. Now we use the volume formula for a 2-ball. Show that (-)
5. Substitute for V. (√) in the integral in Step 3 to confirm again the volume formula for a 3-ball.
Copyright © 2013 Pean Education Ic
Guided Projects
6. The trick used in Steps 3-5 may be used to find the volume of a ball. Vir). When working in >3
dimensions, it's easier to label to coordinates (Recall that the 4-ball is the set
The volume of the 4-ball is given by the inerated integral
V-16
Explain why the inner three integrals qual√
D
To On
Notifications
Messages
check_circle الجواب — حل مفصل خطوة بخطوة
hourglass_top
🔒
الحل الكامل متاح للمشتركين
اشترك في أرشيف الأسئلة لعرض هذا الحل وآلاف الحلول المفصلة خطوة بخطوة من معلمين معتمدين.