(a) Let n be any positive integer. Briefly explain (no formal proofs) why n > 1 ≡ ¬(n = 1).
(b) Recall that a positive integer p is prime iff there do not exist a positive integers n and m, both greater than 1, such that p = nm. (I.e., Prime(p) means ¬∃n ∃m (n > 1 ∧ m > 1 ∧ p = nm).) Give a formal proof of the following: for any prime p, any positive integers n and m satisfying p = nm must satisfy either n = 1 or m = 1. Feel free to use the equivalence from part (a) as the rule “part (a)”.
a) Clearly, (n = 1) is True when n is 1. For any number other than 1, ¬(n = 1) is True. Hence, the statement that if n is a positive integer and n > 1, this implies that n is not equal to 1.
b)
Prime(p) ≡ ¬∃n ∃m (n > 1 ∧ m > 1 ∧ p = nm)
From part (a), n > 1 ≡ ¬(n = 1) and m > 1 ≡ ¬(m = 1), we get
Prime(p) ≡ ¬∃n ∃m (¬(n = 1) ∧ ¬(m = 1) ∧ p = nm)
Prime(p) ≡ ∀n ∀m (¬(¬(n = 1) ∧ ¬(m = 1) ∧ p = nm))
Prime(p) ≡ ∀n ∀m ((n = 1) v (m = 1) v p = nm) (proved)
(a) Let n be any positive integer. Briefly explain (no formal proofs) why n > 1...
1. [10 marks] Modular Arithmetic. The Quotient-Remainder theorem states that given any integer n and a positive integer d there exist unique integers q and r such that n = dq + r and 0 r< d. We define the mod function as follows: (, r r>n = qd+r^0<r< d) Vn,d E Z d0 Z n mod d That is, n mod d is the remainder of n after division by d (a) Translate the following statement into predicate logic:...
Only need 2-5. Need it done ASAP, thank you in advance!!
Proofs 1) (1.7.16) Prove that if m and n are integers and nm is even, then m is even or n is even. * What is the best approach here, direct proof, proof by contraposition, or proof by contradiction why? * Complete the proof. 2) Prove that for any integer n, n is divisible by 3 iff n2 is divisible by 3. Does your proof work for divisibility by...
1) Let n and m be positive integers. Prove: If nm is not divisible by an integer k, then neither n norm is divisible by k. Prove by proving the contrapositive of the statement. Contrapositive of the statement:_ Proof: Direct proof of the contrapositive
Where n is any positive integer, do the following: A. For ε > 0, prove that an converges to a limit of 4 by using the formal definition of convergence of a sequence to a limit, showing all work. 1. Justify each step as part of your proof in A.
For any positive integer n, Euler’s totient or phi function, Φ(n), is the number of positive integers less than n that are relatively prime to n.? What is Φ(55) ?
number thoery
just need 2 answered
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Show that if n is a positive integer and a and b are integers relatively prime to 1 such that (On(a), On(b))1, then
Show that if n is a positive integer and a and b are integers relatively prime to 1 such that (On(a), On(b))1, then
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Let p be a prime, and n a positive integer. Prove that NoTE: This appears to be an infinite sum. Eventulo in fact after a point all of the terms are 0
Part 15A and 15B
(15) Let n E Z+,and let d be a positive divisor of n. Theorem 23.7 tells us that Zn contains exactly one subgroup of order d, but not how many elements Z has of order d. We will determine that number in this exercise. (a) Determine the number of elements in Z12 of each order d. Fill in the table below to compare your answers to the number of integers between 1 and d that are...
Theorem 16.1. Let p be a prime number. Suppose r is a Gaussian integer satisfying N(r) = p. Then r is irreducible in Z[i]. In particular, if a and b are integers such that a² +62 = p, then the Gaussian integers Ea – bi and £b£ai are irreducible. Exercise 16.1. Prove Theorem 16.1. (Hint: For the first part, suppose st is a factorization of r. You must show that this factorization is trivial. Apply the norm to obtain p=...