Number Theory:
Let p be an odd number. Recall that a primitive root, mod p, is
an integer g such that gp-1 = 1 mod p, and no smaller
power of g is congruent to 1 mod p. Some results in this chapter
can be proved via the existence of a primitive root(Theorem
6.26)
(c) Given a primitive root g, and an integer a such that a is
not congruent to 0 mod p, prove that a is a square...
1. Consider the group Zp for a prime p with multiplication
multiplication mod p). Show that (p − 1)2 = 1 (mod p)
2. Is the above true for any number (not necessarily prime)?
3. Show that the equation a 2 − 1 = 0, has only two solutions
mod p.
4. Consider (p − 1)!. Show that (p − 1)! = −1 (mod p) Remark:
Think about what are the values of inverses of 1, 2, . . ....
On a separate sheet of paper, number from 1 to 18. For the 18
spying activities listed as follows, indicate wheter or not you
believe the activity is ethical or unethical AND
legal or illegal. Place either an E for ethical or U for unethical,
and either an L for legal or an I for illegal for each activity.
Compare your answers to those of your classmates and discuss any
differences.
1. Buying competitor's garbage
2. Dissecting competitor's products
?3....
Solve a system of equations:
1-
2x = 5 mod 15
3x = 1 mod 4
2-
x = 5 mod 15
x = 2 mod 12
(Hint: Note that 15 and 12 are not relatively prime. Use the
Chinese remainder
theorem to split the last equation into equations modulo 4 and
modulo 3)
Why does the product of two numbers -having no common factors- that results in a perfect square, make them-the two numbers- perfect squares themselves?