Finite Mathematics (11th Edition)
11th Edition
ISBN: 9780321979438
Author: Margaret L. Lial, Raymond N. Greenwell, Nathan P. Ritchey
Publisher: PEARSON
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Textbook Question
Chapter 2.4, Problem 37E
Given matrices 
verify that the statements in Exercises 36-39 are true. The statements are valid for any matrices whenever matrix multiplication and addition can be carried out. This, of course, depends on the size of the matrices.
P(X + T) = PX + PT (distributive property: see Exercises 29 and 30)
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Students have asked these similar questions
Problem 11 (a) A tank is discharging water through an orifice at a depth of T
meter below the surface of the water whose area is A m². The
following are the values of a for the corresponding values of A:
A 1.257 1.390
x 1.50 1.65
1.520 1.650 1.809 1.962 2.123 2.295 2.462|2.650
1.80 1.95 2.10 2.25 2.40 2.55 2.70
2.85
Using the formula
-3.0
(0.018)T =
dx.
calculate T, the time in seconds for the level of the water to drop
from 3.0 m to 1.5 m above the orifice.
(b) The velocity of a train which starts from rest is given by the fol-
lowing table, the time being reckoned in minutes from the start
and the speed in km/hour:
| † (minutes) |2|4 6 8 10 12
14 16 18 20
v (km/hr) 16 28.8 40 46.4 51.2 32.0 17.6 8 3.2 0
Estimate approximately the total distance ran in 20 minutes.
-
Let n = 7, let p = 23 and let S be the set of least positive residues mod p of the first (p − 1)/2
multiple of n, i.e.
n mod p, 2n mod p, ...,
p-1
2
-n mod p.
Let T be the subset of S consisting of those residues which exceed p/2.
Find the set T, and hence compute the Legendre symbol (7|23).
23
32
how come?
The first 11 multiples of 7 reduced mod 23 are
7, 14, 21, 5, 12, 19, 3, 10, 17, 1, 8.
The set T is the subset of these residues exceeding
So T = {12, 14, 17, 19, 21}.
By Gauss' lemma (Apostol Theorem 9.6),
(7|23) = (−1)|T| = (−1)5 = −1.
Let n = 7, let p = 23 and let S be the set of least positive residues mod p of the first (p-1)/2
multiple of n, i.e.
n mod p, 2n mod p, ...,
2
p-1
-n mod p.
Let T be the subset of S consisting of those residues which exceed p/2.
Find the set T, and hence compute the Legendre symbol (7|23).
The first 11 multiples of 7 reduced mod 23 are
7, 14, 21, 5, 12, 19, 3, 10, 17, 1, 8.
23
The set T is the subset of these residues exceeding
2°
So T = {12, 14, 17, 19, 21}.
By Gauss' lemma (Apostol Theorem 9.6),
(7|23) = (−1)|T| = (−1)5 = −1.
how come?
Chapter 2 Solutions
Finite Mathematics (11th Edition)
Ch. 2.1 - Use the echelon method to solve each system of two...Ch. 2.1 - Use the echelon method to solve each system of two...Ch. 2.1 -
Use the echelon method to solve each system of...Ch. 2.1 - Use the echelon method to solve each system of two...Ch. 2.1 - Prob. 5ECh. 2.1 - Prob. 6ECh. 2.1 - Prob. 7ECh. 2.1 -
Use the echelon method to solve each system of...Ch. 2.1 - Prob. 9ECh. 2.1 - Prob. 10E
Ch. 2.1 -
Use the echelon method to solve each system of...Ch. 2.1 - Use the echelon method to solve each system of two...Ch. 2.1 - Use the echelon method to solve each system of two...Ch. 2.1 - Use the echelon method to solve each system of two...Ch. 2.1 - Prob. 15ECh. 2.1 - Use the echelon method to solve each system of two...Ch. 2.1 - Prob. 17ECh. 2.1 - Use the echelon method to solve each system of two...Ch. 2.1 - Use the echelon method to solve each system of two...Ch. 2.1 - Prob. 20ECh. 2.1 - An inconsistent system...Ch. 2.1 - Prob. 22ECh. 2.1 - Describe what a parameter is arid why it is used...Ch. 2.1 - In your own words, describe the echelon method as...Ch. 2.1 - Prob. 25ECh. 2.1 - Solve each system of equations. Let z be the...Ch. 2.1 - Solve each system of equations. Let z be the...Ch. 2.1 - Prob. 28ECh. 2.1 - Prob. 29ECh. 2.1 - For each of the following systems of equations in...Ch. 2.1 -
For each of the following systems of equations in...Ch. 2.1 - Prob. 32ECh. 2.1 - Prob. 33ECh. 2.1 - Prob. 34ECh. 2.1 -
Groceries If 20 lb of rice and 10 lb of potatoes...Ch. 2.1 -
36. Downloads Blake Allvine spent $35.97...Ch. 2.1 - Prob. 37ECh. 2.1 -
38. Sales An apparel shop sells skirts for $45...Ch. 2.1 - Prob. 39ECh. 2.1 -
40. Stock Lorri Morgan has $16,000 invested in...Ch. 2.1 - Banking A bank teller has a total of 70 bills in...Ch. 2.1 - Rug Cleaning Machines Kelly Karpet Kleaners sells...Ch. 2.1 - Prob. 43ECh. 2.1 - Prob. 44ECh. 2.1 - Prob. 45ECh. 2.1 - Prob. 46ECh. 2.1 - Prob. 47ECh. 2.1 -
48. Flight Time A flight leaves New York at 8...Ch. 2.1 -
49. The 24® Game The object of the 24 Game,...Ch. 2.2 -
Write the augmented matrix fur each system. Do...Ch. 2.2 -
Write the augmented matrix for each system. Do...Ch. 2.2 - Prob. 3ECh. 2.2 - Prob. 4ECh. 2.2 - Prob. 5ECh. 2.2 - Prob. 6ECh. 2.2 -
Write the system of equations associated with...Ch. 2.2 - Prob. 8ECh. 2.2 - Prob. 9ECh. 2.2 - Prob. 10ECh. 2.2 - Prob. 11ECh. 2.2 - Use the indicated row operations to change each...Ch. 2.2 - Prob. 13ECh. 2.2 - Prob. 14ECh. 2.2 - Prob. 15ECh. 2.2 - Prob. 16ECh. 2.2 - Prob. 17ECh. 2.2 - Prob. 18ECh. 2.2 - Prob. 19ECh. 2.2 - Prob. 20ECh. 2.2 - Use the Gauss-Jordan method to solve each system...Ch. 2.2 - Use the Gauss-Jordan method to solve each system...Ch. 2.2 - Prob. 23ECh. 2.2 - Prob. 24ECh. 2.2 - Prob. 25ECh. 2.2 - Use the Gauss-Jordan method to solve each system...Ch. 2.2 - Prob. 27ECh. 2.2 -
Use the Gauss-Jordan method to solve each system...Ch. 2.2 - Prob. 29ECh. 2.2 - Prob. 30ECh. 2.2 - Prob. 31ECh. 2.2 - Prob. 32ECh. 2.2 - Prob. 33ECh. 2.2 - Prob. 34ECh. 2.2 - Prob. 35ECh. 2.2 - Prob. 36ECh. 2.2 - Prob. 37ECh. 2.2 - Prob. 38ECh. 2.2 - Prob. 39ECh. 2.2 - Prob. 40ECh. 2.2 - Prob. 41ECh. 2.2 - Prob. 42ECh. 2.2 -
43. On National Public Radio, the "Weekend...Ch. 2.2 - Prob. 44ECh. 2.2 - Investments Katherine Chong invests $10,000...Ch. 2.2 -
46. Office Technology Pyro-Tech, Inc. is...Ch. 2.2 - Prob. 47ECh. 2.2 - Prob. 48ECh. 2.2 - Loans To get the necessary funds for a planned...Ch. 2.2 - Manufacturing Nadir, Inc. produces three models of...Ch. 2.2 -
51. Deliveries An electronics company produces...Ch. 2.2 - Tents L.L. Bean makes three sizes of Ultra Dome...Ch. 2.2 - Transportation A manufacturer purchases a part for...Ch. 2.2 - APPLY IT Transportation An auto manufacturer sends...Ch. 2.2 - Prob. 55ECh. 2.2 -
56. Packaging A company produces four...Ch. 2.2 - Prob. 57ECh. 2.2 - Animal Breeding An animal breeder can buy four...Ch. 2.2 - Prob. 59ECh. 2.2 - Prob. 60ECh. 2.2 - Prob. 61ECh. 2.2 - Prob. 62ECh. 2.2 - Prob. 63ECh. 2.2 - Prob. 64ECh. 2.2 -
65. Modeling War One of the factors that...Ch. 2.2 - Prob. 66ECh. 2.2 -
67. Baseball Ichiro Suzuki holds the American...Ch. 2.2 - Prob. 68ECh. 2.2 -
69. Toys One hundred toys are to be given out to...Ch. 2.2 - Prob. 70ECh. 2.2 - Prob. 71ECh. 2.2 - Prob. 72ECh. 2.2 - Prob. 73ECh. 2.3 - Prob. 1ECh. 2.3 - Prob. 2ECh. 2.3 - Prob. 3ECh. 2.3 - Prob. 4ECh. 2.3 - Decide whether each statement is true or false. If...Ch. 2.3 - Prob. 6ECh. 2.3 - Prob. 7ECh. 2.3 - Prob. 8ECh. 2.3 - Prob. 9ECh. 2.3 - Prob. 10ECh. 2.3 - Prob. 11ECh. 2.3 - Prob. 12ECh. 2.3 - Prob. 13ECh. 2.3 - Prob. 14ECh. 2.3 - Prob. 15ECh. 2.3 - Prob. 16ECh. 2.3 - Prob. 17ECh. 2.3 - Prob. 18ECh. 2.3 - Prob. 19ECh. 2.3 - Prob. 20ECh. 2.3 - Prob. 21ECh. 2.3 - Prob. 22ECh. 2.3 - Prob. 23ECh. 2.3 - Prob. 24ECh. 2.3 - Prob. 25ECh. 2.3 - Prob. 26ECh. 2.3 - Prob. 27ECh. 2.3 - Prob. 28ECh. 2.3 - Prob. 29ECh. 2.3 - Prob. 30ECh. 2.3 - Prob. 31ECh. 2.3 - Prob. 32ECh. 2.3 - For matrices X=[ xyzw] and 0=[ 0000], find the...Ch. 2.3 - Prob. 34ECh. 2.3 - Prob. 35ECh. 2.3 - Prob. 36ECh. 2.3 - Prob. 37ECh. 2.3 - Prob. 38ECh. 2.3 - Prob. 39ECh. 2.3 - Prob. 40ECh. 2.3 - Prob. 41ECh. 2.3 -
42. Trading Partners The table below gives, the...Ch. 2.3 - Prob. 43ECh. 2.3 - Prob. 44ECh. 2.3 - Testing Medication A drug company is testing 200...Ch. 2.3 - Prob. 46ECh. 2.3 - Prob. 47ECh. 2.3 - Prob. 48ECh. 2.3 - Prob. 49ECh. 2.3 - Prob. 50ECh. 2.4 - Let A=[ -2-403] and B=[ -6240]. Find each value....Ch. 2.4 - Prob. 2ECh. 2.4 - Prob. 3ECh. 2.4 - Prob. 4ECh. 2.4 - Prob. 5ECh. 2.4 -
Let and Find each value.
6. 7B– 3A
Ch. 2.4 - Prob. 7ECh. 2.4 - Prob. 8ECh. 2.4 - Prob. 9ECh. 2.4 - Prob. 10ECh. 2.4 - Prob. 11ECh. 2.4 - Prob. 12ECh. 2.4 - To find the product matrix AB, the number of...Ch. 2.4 - Prob. 14ECh. 2.4 - Prob. 15ECh. 2.4 - Prob. 16ECh. 2.4 - Prob. 17ECh. 2.4 - Prob. 18ECh. 2.4 -
Find each matrix product, if possible.
19.
Ch. 2.4 - Find each matrix product, if possible. [...Ch. 2.4 - Prob. 21ECh. 2.4 - Prob. 22ECh. 2.4 - Prob. 23ECh. 2.4 - Prob. 24ECh. 2.4 - Prob. 25ECh. 2.4 - Prob. 26ECh. 2.4 - Prob. 27ECh. 2.4 - Prob. 28ECh. 2.4 - Prob. 29ECh. 2.4 - Prob. 30ECh. 2.4 - Prob. 31ECh. 2.4 - Prob. 32ECh. 2.4 - Prob. 33ECh. 2.4 - Prob. 34ECh. 2.4 - Prob. 35ECh. 2.4 - Prob. 36ECh. 2.4 -
Given matrices
verify that the statements in...Ch. 2.4 - Prob. 38ECh. 2.4 - Prob. 39ECh. 2.4 - Prob. 40ECh. 2.4 - Prob. 41ECh. 2.4 - Prob. 42ECh. 2.4 - Use a computer or graphing calculator arid the...Ch. 2.4 - Prob. 44ECh. 2.4 - Prob. 45ECh. 2.4 - Prob. 46ECh. 2.4 - Prob. 47ECh. 2.4 - Prob. 48ECh. 2.4 - Prob. 49ECh. 2.4 - Prob. 50ECh. 2.4 - Prob. 51ECh. 2.4 - Prob. 52ECh. 2.4 - Prob. 53ECh. 2.4 - Prob. 54ECh. 2.4 - Prob. 55ECh. 2.4 - 56. Northern Spotted Owl Population In an attempt...Ch. 2.4 -
57. World Population The 2010 birth and death...Ch. 2.5 - Prob. 1ECh. 2.5 -
Decide whether the given matrices are inverses...Ch. 2.5 - Prob. 3ECh. 2.5 - Decide whether the given matrices are inverses of...Ch. 2.5 - Decide whether the given matrices are inverses of...Ch. 2.5 - Prob. 6ECh. 2.5 - Prob. 7ECh. 2.5 - Prob. 8ECh. 2.5 - Prob. 9ECh. 2.5 - Prob. 10ECh. 2.5 - Prob. 11ECh. 2.5 - Prob. 12ECh. 2.5 - Prob. 13ECh. 2.5 - Prob. 14ECh. 2.5 - Prob. 15ECh. 2.5 - Prob. 16ECh. 2.5 - Prob. 17ECh. 2.5 - Prob. 18ECh. 2.5 - Prob. 19ECh. 2.5 - Prob. 20ECh. 2.5 - Prob. 21ECh. 2.5 - Prob. 22ECh. 2.5 - Find the inverse, if it exists, for each matrix. [...Ch. 2.5 - Prob. 24ECh. 2.5 - Prob. 25ECh. 2.5 - Prob. 26ECh. 2.5 - Prob. 27ECh. 2.5 -
Solve each system of equations by using the...Ch. 2.5 -
Solve each system of equations by using the...Ch. 2.5 - Prob. 30ECh. 2.5 - Prob. 31ECh. 2.5 - Prob. 32ECh. 2.5 - Prob. 33ECh. 2.5 -
Solve each system of equations by using the...Ch. 2.5 -
Solve each system of equations by using the...Ch. 2.5 - Prob. 36ECh. 2.5 - Prob. 37ECh. 2.5 - Prob. 38ECh. 2.5 - Prob. 39ECh. 2.5 - Prob. 40ECh. 2.5 - Prob. 41ECh. 2.5 - Prob. 42ECh. 2.5 - Prob. 43ECh. 2.5 - Prob. 44ECh. 2.5 - Prob. 45ECh. 2.5 - Prob. 46ECh. 2.5 - Prob. 47ECh. 2.5 - Prob. 48ECh. 2.5 - Prob. 49ECh. 2.5 - Prob. 50ECh. 2.5 - Prob. 51ECh. 2.5 - Prob. 52ECh. 2.5 - Prob. 53ECh. 2.5 - Prob. 54ECh. 2.5 - Prob. 55ECh. 2.5 - Prob. 56ECh. 2.5 - Prob. 57ECh. 2.5 - Prob. 58ECh. 2.5 - Prob. 59ECh. 2.5 - Prob. 60ECh. 2.5 - Prob. 61ECh. 2.5 - Solve each exercise by using the inverse of the...Ch. 2.5 - Prob. 63ECh. 2.5 -
Solve each exercise by using the inverse of the...Ch. 2.5 - Prob. 65ECh. 2.5 -
Solve each exercise by using the inverse of the...Ch. 2.6 -
Find the production matrix for the following...Ch. 2.6 - Prob. 2ECh. 2.6 - Prob. 3ECh. 2.6 - Prob. 4ECh. 2.6 - Prob. 5ECh. 2.6 - Prob. 6ECh. 2.6 - Prob. 7ECh. 2.6 - Find the ratios of products A, B, and C using a...Ch. 2.6 - Prob. 9ECh. 2.6 - Use a graphing calculator or computer to find the...Ch. 2.6 - Prob. 11ECh. 2.6 -
Input-Output Open Model In Exercises 11 and 12,...Ch. 2.6 - Prob. 13ECh. 2.6 - Prob. 14ECh. 2.6 - Input-Output Open Model In Exercises 13-16, refer...Ch. 2.6 - Input-Output Open Model In Exercises 13- refer to...Ch. 2.6 - Input-Output Open Model A primitive economy...Ch. 2.6 - Prob. 18ECh. 2.6 - Prob. 19ECh. 2.6 - Prob. 20ECh. 2.6 -
21. Israeli Economy An analysis of the 1958...Ch. 2.6 -
22. Chinese Economy The 1981 Chinese economy can...Ch. 2.6 - Prob. 23ECh. 2.6 - Prob. 24ECh. 2.6 - Prob. 25ECh. 2.6 - Prob. 26ECh. 2.6 -
27. Input-Output Closed Model Use the...Ch. 2.6 - Input-Output Closed Model Suppose that production...Ch. 2.6 - Prob. 29ECh. 2 - Find the second-order contact matrix PQ mentioned...Ch. 2 - Prob. 2EACh. 2 - Prob. 3EACh. 2 - Prob. 4EACh. 2 - Prob. 5EACh. 2 - Prob. 1RECh. 2 - Determine whether each of the following statements...Ch. 2 - Prob. 3RECh. 2 - Prob. 4RECh. 2 - Prob. 5RECh. 2 - Prob. 6RECh. 2 - Prob. 7RECh. 2 - Prob. 8RECh. 2 - Prob. 9RECh. 2 - Prob. 10RECh. 2 - Prob. 11RECh. 2 - Prob. 12RECh. 2 - Prob. 13RECh. 2 - Prob. 14RECh. 2 - Prob. 15RECh. 2 - Prob. 16RECh. 2 - Prob. 17RECh. 2 - Prob. 18RECh. 2 -
Solve each system by the echelon method.
19. 2x -...Ch. 2 - Prob. 20RECh. 2 - Solve each system by the echelon method. 2x - 3y +...Ch. 2 - Prob. 22RECh. 2 - Prob. 23RECh. 2 - Prob. 24RECh. 2 - Prob. 25RECh. 2 - Prob. 26RECh. 2 - Prob. 27RECh. 2 - Prob. 28RECh. 2 - Prob. 29RECh. 2 - Prob. 30RECh. 2 - Prob. 31RECh. 2 - Prob. 32RECh. 2 - Prob. 33RECh. 2 - Prob. 34RECh. 2 - Prob. 35RECh. 2 - Prob. 36RECh. 2 - Prob. 37RECh. 2 - Prob. 38RECh. 2 - Prob. 39RECh. 2 - Given the matrices A=[ 4102369],B=[ 232240012],C=[...Ch. 2 - Prob. 41RECh. 2 - Prob. 42RECh. 2 - Prob. 43RECh. 2 - Prob. 44RECh. 2 - Prob. 45RECh. 2 - Prob. 46RECh. 2 - Prob. 47RECh. 2 - Prob. 48RECh. 2 - Prob. 49RECh. 2 - Prob. 50RECh. 2 - Prob. 51RECh. 2 - Find the inverse of each matrix that has an...Ch. 2 - Prob. 53RECh. 2 - Prob. 54RECh. 2 - Prob. 55RECh. 2 - Prob. 56RECh. 2 - Prob. 57RECh. 2 - Prob. 58RECh. 2 - Prob. 59RECh. 2 - Prob. 60RECh. 2 - Prob. 61RECh. 2 - Prob. 62RECh. 2 - Prob. 63RECh. 2 - Prob. 64RECh. 2 - Prob. 65RECh. 2 - Prob. 66RECh. 2 - Prob. 67RECh. 2 - Prob. 68RECh. 2 - Prob. 69RECh. 2 - Prob. 70RECh. 2 - Prob. 71RECh. 2 - Filling Orders A printer has three orders for...Ch. 2 -
73. Input-Output An economy depends on two...Ch. 2 -
74. Nebraska The 1970 economy of the state of...Ch. 2 - Prob. 75RECh. 2 - Prob. 76RECh. 2 - Prob. 77RECh. 2 - Prob. 78RECh. 2 - Prob. 79RECh. 2 - Prob. 80RECh. 2 - Prob. 81RECh. 2 - Prob. 82RECh. 2 - Prob. 83RECh. 2 -
84. Baseball In the 2009 Major League Baseball...Ch. 2 - Prob. 85RE
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