3. Show that ifn = 2 (mod 4), then 9" + 8" is divisible by 5.

Advanced Engineering Mathematics
10th Edition
ISBN:9780470458365
Author:Erwin Kreyszig
Publisher:Erwin Kreyszig
Chapter2: Second-order Linear Odes
Section: Chapter Questions
Problem 1RQ
icon
Related questions
Topic Video
Question
Can you do #3?
Exercises for Section 4.1
1. Use Fermat's Theorem to compute the following quantities.
(a) 31100 mod 19.
(b) 210000 mod 29.
(c) 99999 mod 31.
-2. Show that 1184 – 584 is divisible by 7.
3. Show that if n = 2 (mod 4), then 9" + 8" is divisible by 5.
4. For which values of n is 3" + 2" divisible by 13? by 7?
n is divisible by 2730 for all -
ba? is divisible by 6p.
5. Use Fermat's Theorem to show that n13
6. Show that if p> 3 is prime, then ab"
7. Show, using the Binomial Theorem, that if p is prime and a and b are int
gers,
then (a + b)P = a + b (mod p).
8. Show that no prime number of the form 4k + 3 can divide a number of th
form n2 + 1.
9. Show that there are infinitely many primes of the form 16k + 1. More
generally, show that for any r > 0, there are infinitely many primes of the
form 2" k + 1.
10. Let n = r4 +1. Show that 3, 5, and 7 cannot divide n. What is the smallest
prime that can divide n? Determine the form of the prime divisors of n.
11. Show that any proper factor, whether prime or not, of a composite Mersenne
number 2P – 1 is of the form 1 + 2pk for some k.
12. What can you say about the prime factors of a composite Fermat number
Fn = 22" +1? Use Fermat's Theorem and Proposition 4.1.5 to find a factor
of F5, thereby disproving Fermat's statement that all the Fn are prime.
13. In 1909, Wiefrich proved that if p is prime and xP + yP = zP has integer
solutions withpt ryz, then p satisfies 2P-1 = 1 (mod p²). A prime p
satisfying this latter congruence is called a Winfrinh
first two
Transcribed Image Text:Exercises for Section 4.1 1. Use Fermat's Theorem to compute the following quantities. (a) 31100 mod 19. (b) 210000 mod 29. (c) 99999 mod 31. -2. Show that 1184 – 584 is divisible by 7. 3. Show that if n = 2 (mod 4), then 9" + 8" is divisible by 5. 4. For which values of n is 3" + 2" divisible by 13? by 7? n is divisible by 2730 for all - ba? is divisible by 6p. 5. Use Fermat's Theorem to show that n13 6. Show that if p> 3 is prime, then ab" 7. Show, using the Binomial Theorem, that if p is prime and a and b are int gers, then (a + b)P = a + b (mod p). 8. Show that no prime number of the form 4k + 3 can divide a number of th form n2 + 1. 9. Show that there are infinitely many primes of the form 16k + 1. More generally, show that for any r > 0, there are infinitely many primes of the form 2" k + 1. 10. Let n = r4 +1. Show that 3, 5, and 7 cannot divide n. What is the smallest prime that can divide n? Determine the form of the prime divisors of n. 11. Show that any proper factor, whether prime or not, of a composite Mersenne number 2P – 1 is of the form 1 + 2pk for some k. 12. What can you say about the prime factors of a composite Fermat number Fn = 22" +1? Use Fermat's Theorem and Proposition 4.1.5 to find a factor of F5, thereby disproving Fermat's statement that all the Fn are prime. 13. In 1909, Wiefrich proved that if p is prime and xP + yP = zP has integer solutions withpt ryz, then p satisfies 2P-1 = 1 (mod p²). A prime p satisfying this latter congruence is called a Winfrinh first two
Expert Solution
steps

Step by step

Solved in 2 steps with 1 images

Blurred answer
Knowledge Booster
Discrete Probability Distributions
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, advanced-math and related others by exploring similar questions and additional content below.
Recommended textbooks for you
Advanced Engineering Mathematics
Advanced Engineering Mathematics
Advanced Math
ISBN:
9780470458365
Author:
Erwin Kreyszig
Publisher:
Wiley, John & Sons, Incorporated
Numerical Methods for Engineers
Numerical Methods for Engineers
Advanced Math
ISBN:
9780073397924
Author:
Steven C. Chapra Dr., Raymond P. Canale
Publisher:
McGraw-Hill Education
Introductory Mathematics for Engineering Applicat…
Introductory Mathematics for Engineering Applicat…
Advanced Math
ISBN:
9781118141809
Author:
Nathan Klingbeil
Publisher:
WILEY
Mathematics For Machine Technology
Mathematics For Machine Technology
Advanced Math
ISBN:
9781337798310
Author:
Peterson, John.
Publisher:
Cengage Learning,
Basic Technical Mathematics
Basic Technical Mathematics
Advanced Math
ISBN:
9780134437705
Author:
Washington
Publisher:
PEARSON
Topology
Topology
Advanced Math
ISBN:
9780134689517
Author:
Munkres, James R.
Publisher:
Pearson,