BuyFindarrow_forward

Elements Of Modern Algebra

8th Edition
Gilbert + 2 others
ISBN: 9781285463230

Solutions

Chapter
Section
BuyFindarrow_forward

Elements Of Modern Algebra

8th Edition
Gilbert + 2 others
ISBN: 9781285463230
Textbook Problem

Suppose the alphabet consists of a through z , in natural order, followed by a blank, a comma, and a period, in that order. Associate these "letters" with the numbers 0 ,   1 ,   2 ,   ...   ,   28 , respectively, thus forming a 29 -letter alphabet, E . Use the affine cipher to decipher the message

B Z Z K , A U Z N Z G, R S K Z , A U W A O if you know that the plaintext message begins with " b " and ends with ".". Write out the affine mapping f and its inverse.

To determine

Plain text in the 29 letter alphabet E, by using the affine cipher to decipher the message “ BZZK, AUZNZG, RSKZ, AUWAO” and the plain text message begins with “b” followed by “.” Write down the affine mapping f and f1.

Explanation

Given information:

(i) The 29-letter alphabet D -

If alphabet consist of a to z, in natural order followed by blank, a comma and a period, then have 29 “letters” that associates with the integer 0,1,2,3,...,28 as follows:

Alphabet: abcdef...vwxyz"blank"commaperiod

D:012345...2122232425262728

ii) Euclidean Algorithm:

Let a and b are integers with b>0, then the procedure

a=bq0+r10r1<bb=r1q1+r20r2<r1r1=r2q2+r30r3<r2rk=rk+1qk+1+rk+20rk+2<rk+1

is known as Euclidean Algorithm.

Since the integers r1,r2,,rk+2 are decreasing and are all non-negative, there is a smallest integer n, such that rn+1=0:

rn1=rnqn+rn+10=rn+1

If r0=b, then the last non-zero remainder rn is always greatest common divisor of a and b.

Formula used:

Affine cipher:

Define the mapping f:AA by f(x)=ax+bmodn. Where a,b are fixed integers and order pair a,b forms a key to affine cipher.

Calculation:

As plaintext begins with “b” and ends with “.”

The ciphertext B and O corresponds to the plain text “b” and ”.”.

Translating these into the set D,

BtranslatetoE1btranslatetoE1

OtranslatetoE14.translatetoE28

Now, to determine the key from the following system of equations for a and b.

1=a(1)+bmod2914=a(28)+bmod29

Use a=b(modn)b=a(modn)

a(1)+b=1mod29…… (1)

a(28)+b=14mod29…… (2)

Subtract (1) from (2), gives

a(28)a(1)=141mod29

a(27)=13mod29

27a=13mod29

Now, to find the multiplicative inverse of 27 using Euclidean algorithm.

29=27+2

27=13(2)+1

Thus,

1=2713(2)

1=2713(2927)

1=2713(29)+13(27)

1=27(14)13(29)

Thus, 27(14)=1(mod29)

The inverse 271=14(mod29).

Consider, 27a=13(mod29)

a=27113(mod29)

a=(14)13(mod29)

a=182(mod29)

a=8(mod29)

Now, from (1), a(1)+b=1mod29

(8(mod29))(1)+b=1mod29

b=8(mod29)+1(mod29)

b=8+1(mod29)

b=7(mod29)

b=22(mod29) as 22=7(mod29)

Therefore, a=8 and b=22 is the solution of the system

Still sussing out bartleby?

Check out a sample textbook solution.

See a sample solution

The Solution to Your Study Problems

Bartleby provides explanations to thousands of textbook problems written by our experts, many with advanced degrees!

Get Started
Sect-2.1 P-1ESect-2.1 P-2ESect-2.1 P-3ESect-2.1 P-4ESect-2.1 P-5ESect-2.1 P-6ESect-2.1 P-7ESect-2.1 P-8ESect-2.1 P-9ESect-2.1 P-10ESect-2.1 P-11ESect-2.1 P-12ESect-2.1 P-13ESect-2.1 P-14ESect-2.1 P-15ESect-2.1 P-16ESect-2.1 P-17ESect-2.1 P-18ESect-2.1 P-19ESect-2.1 P-20ESect-2.1 P-21ESect-2.1 P-22ESect-2.1 P-23ESect-2.1 P-24ESect-2.1 P-25ESect-2.1 P-26ESect-2.1 P-27ESect-2.1 P-28ESect-2.1 P-29ESect-2.1 P-30ESect-2.1 P-31ESect-2.1 P-32ESect-2.1 P-33ESect-2.1 P-34ESect-2.1 P-35ESect-2.2 P-1ESect-2.2 P-2ESect-2.2 P-3ESect-2.2 P-4ESect-2.2 P-5ESect-2.2 P-6ESect-2.2 P-7ESect-2.2 P-8ESect-2.2 P-9ESect-2.2 P-10ESect-2.2 P-11ESect-2.2 P-12ESect-2.2 P-13ESect-2.2 P-14ESect-2.2 P-15ESect-2.2 P-16ESect-2.2 P-17ESect-2.2 P-18ESect-2.2 P-19ESect-2.2 P-20ESect-2.2 P-21ESect-2.2 P-22ESect-2.2 P-23ESect-2.2 P-24ESect-2.2 P-25ESect-2.2 P-26ESect-2.2 P-27ESect-2.2 P-28ESect-2.2 P-29ESect-2.2 P-30ESect-2.2 P-31ESect-2.2 P-32ESect-2.2 P-33ESect-2.2 P-34ESect-2.2 P-35ESect-2.2 P-36ESect-2.2 P-37ESect-2.2 P-38ESect-2.2 P-39ESect-2.2 P-40ESect-2.2 P-41ESect-2.2 P-42ESect-2.2 P-43ESect-2.2 P-44ESect-2.2 P-45ESect-2.2 P-46ESect-2.2 P-47ESect-2.2 P-48ESect-2.2 P-49ESect-2.2 P-50ESect-2.2 P-51ESect-2.2 P-52ESect-2.2 P-53ESect-2.2 P-54ESect-2.2 P-55ESect-2.2 P-56ESect-2.2 P-57ESect-2.3 P-1TFESect-2.3 P-2TFESect-2.3 P-3TFESect-2.3 P-4TFESect-2.3 P-5TFESect-2.3 P-6TFESect-2.3 P-7TFESect-2.3 P-8TFESect-2.3 P-9TFESect-2.3 P-10TFESect-2.3 P-1ESect-2.3 P-2ESect-2.3 P-3ESect-2.3 P-4ESect-2.3 P-5ESect-2.3 P-6ESect-2.3 P-7ESect-2.3 P-8ESect-2.3 P-9ESect-2.3 P-10ESect-2.3 P-11ESect-2.3 P-12ESect-2.3 P-13ESect-2.3 P-14ESect-2.3 P-15ESect-2.3 P-16ESect-2.3 P-17ESect-2.3 P-18ESect-2.3 P-19ESect-2.3 P-20ESect-2.3 P-21ESect-2.3 P-22ESect-2.3 P-23ESect-2.3 P-24ESect-2.3 P-25ESect-2.3 P-26ESect-2.3 P-27ESect-2.3 P-28ESect-2.3 P-29ESect-2.3 P-30ESect-2.3 P-31ESect-2.3 P-32ESect-2.3 P-33ESect-2.3 P-34ESect-2.3 P-35ESect-2.3 P-36ESect-2.3 P-37ESect-2.3 P-38ESect-2.3 P-39ESect-2.3 P-40ESect-2.3 P-41ESect-2.3 P-42ESect-2.3 P-43ESect-2.3 P-44ESect-2.3 P-45ESect-2.3 P-46ESect-2.3 P-47ESect-2.3 P-48ESect-2.3 P-49ESect-2.4 P-1TFESect-2.4 P-2TFESect-2.4 P-3TFESect-2.4 P-4TFESect-2.4 P-5TFESect-2.4 P-6TFESect-2.4 P-7TFESect-2.4 P-8TFESect-2.4 P-9TFESect-2.4 P-10TFESect-2.4 P-11TFESect-2.4 P-12TFESect-2.4 P-13TFESect-2.4 P-1ESect-2.4 P-2ESect-2.4 P-3ESect-2.4 P-4ESect-2.4 P-5ESect-2.4 P-6ESect-2.4 P-7ESect-2.4 P-8ESect-2.4 P-9ESect-2.4 P-10ESect-2.4 P-11ESect-2.4 P-12ESect-2.4 P-13ESect-2.4 P-14ESect-2.4 P-15ESect-2.4 P-16ESect-2.4 P-17ESect-2.4 P-18ESect-2.4 P-19ESect-2.4 P-20ESect-2.4 P-21ESect-2.4 P-22ESect-2.4 P-23ESect-2.4 P-24ESect-2.4 P-25ESect-2.4 P-26ESect-2.4 P-27ESect-2.4 P-28ESect-2.4 P-29ESect-2.4 P-30ESect-2.4 P-31ESect-2.4 P-32ESect-2.4 P-33ESect-2.4 P-34ESect-2.4 P-35ESect-2.5 P-1TFESect-2.5 P-2TFESect-2.5 P-3TFESect-2.5 P-4TFESect-2.5 P-5TFESect-2.5 P-6TFESect-2.5 P-7TFESect-2.5 P-1ESect-2.5 P-2ESect-2.5 P-3ESect-2.5 P-4ESect-2.5 P-5ESect-2.5 P-6ESect-2.5 P-7ESect-2.5 P-8ESect-2.5 P-9ESect-2.5 P-10ESect-2.5 P-11ESect-2.5 P-12ESect-2.5 P-13ESect-2.5 P-14ESect-2.5 P-15ESect-2.5 P-16ESect-2.5 P-17ESect-2.5 P-18ESect-2.5 P-19ESect-2.5 P-20ESect-2.5 P-21ESect-2.5 P-22ESect-2.5 P-23ESect-2.5 P-24ESect-2.5 P-25ESect-2.5 P-26ESect-2.5 P-27ESect-2.5 P-28ESect-2.5 P-29ESect-2.5 P-30ESect-2.5 P-31ESect-2.5 P-32ESect-2.5 P-33ESect-2.5 P-34ESect-2.5 P-35ESect-2.5 P-36ESect-2.5 P-37ESect-2.5 P-38ESect-2.5 P-39ESect-2.5 P-40ESect-2.5 P-41ESect-2.5 P-42ESect-2.5 P-43ESect-2.5 P-44ESect-2.5 P-45ESect-2.5 P-46ESect-2.5 P-47ESect-2.5 P-48ESect-2.5 P-49ESect-2.5 P-50ESect-2.5 P-51ESect-2.5 P-52ESect-2.5 P-53ESect-2.5 P-54ESect-2.5 P-55ESect-2.5 P-56ESect-2.5 P-57ESect-2.5 P-58ESect-2.6 P-1TFESect-2.6 P-2TFESect-2.6 P-3TFESect-2.6 P-4TFESect-2.6 P-5TFESect-2.6 P-6TFESect-2.6 P-7TFESect-2.6 P-8TFESect-2.6 P-1ESect-2.6 P-2ESect-2.6 P-3ESect-2.6 P-4ESect-2.6 P-5ESect-2.6 P-6ESect-2.6 P-7ESect-2.6 P-8ESect-2.6 P-9ESect-2.6 P-10ESect-2.6 P-11ESect-2.6 P-12ESect-2.6 P-13ESect-2.6 P-14ESect-2.6 P-15ESect-2.6 P-16ESect-2.6 P-17ESect-2.6 P-18ESect-2.6 P-19ESect-2.6 P-20ESect-2.6 P-21ESect-2.6 P-22ESect-2.6 P-23ESect-2.6 P-24ESect-2.6 P-25ESect-2.6 P-26ESect-2.7 P-1TFESect-2.7 P-2TFESect-2.7 P-3TFESect-2.7 P-4TFESect-2.7 P-1ESect-2.7 P-2ESect-2.7 P-3ESect-2.7 P-4ESect-2.7 P-5ESect-2.7 P-6ESect-2.7 P-7ESect-2.7 P-8ESect-2.7 P-9ESect-2.7 P-10ESect-2.7 P-11ESect-2.7 P-12ESect-2.7 P-13ESect-2.7 P-14ESect-2.7 P-15ESect-2.7 P-16ESect-2.7 P-17ESect-2.7 P-18ESect-2.7 P-19ESect-2.7 P-20ESect-2.7 P-21ESect-2.7 P-22ESect-2.7 P-23ESect-2.7 P-24ESect-2.7 P-25ESect-2.7 P-26ESect-2.8 P-1TFESect-2.8 P-2TFESect-2.8 P-3TFESect-2.8 P-1ESect-2.8 P-2ESect-2.8 P-3ESect-2.8 P-4ESect-2.8 P-5ESect-2.8 P-6ESect-2.8 P-7ESect-2.8 P-8ESect-2.8 P-9ESect-2.8 P-10ESect-2.8 P-11ESect-2.8 P-12ESect-2.8 P-13ESect-2.8 P-14ESect-2.8 P-15ESect-2.8 P-16ESect-2.8 P-17ESect-2.8 P-18ESect-2.8 P-19ESect-2.8 P-20ESect-2.8 P-21ESect-2.8 P-22ESect-2.8 P-23ESect-2.8 P-24ESect-2.8 P-25ESect-2.8 P-26E

Additional Math Solutions

Find more solutions based on key concepts

Show solutions add

Market Equilibrium for Digital Cameras The quantity demanded x (in units of a hundred) of Mikado digital camera...

Applied Calculus for the Managerial, Life, and Social Sciences: A Brief Approach

Draw the graph of each equation: y=3

Elementary Technical Mathematics

y=4x2+1 defines y implicitly as a function of x.

Study Guide for Stewart's Single Variable Calculus: Early Transcendentals, 8th

The gradient vector field for is:

Study Guide for Stewart's Multivariable Calculus, 8th