Proof by contradiction: Suppose a right triangle has side
lengths a, b, c that are natural...
Proof by contradiction: Suppose a right triangle has side
lengths a, b, c that are natural numbers. Prove that at least one
of a, b, or c must be even. (Hint: Use Pythagorean Theorem)
In class we proved that if (x, y, z) is a primitive Pythagorean
triple, then (switching...
In class we proved that if (x, y, z) is a primitive Pythagorean
triple, then (switching x and y if necessary) it must be that (x,
y, z) = (m2 − n 2 , 2mn, m2 + n 2 ) for some positive integers m
and n satisfying m > n, gcd(m, n) = 1, and either m or n is
even. In this question you will prove that the converse is true: if
m and n are integers satisfying...
Prove: Let (a,b,c) be a primitive pythagorean triple. then we
have the following
1. gcd(c-b, c+b)...
Prove: Let (a,b,c) be a primitive pythagorean triple. then we
have the following
1. gcd(c-b, c+b) =1
2. c-b and c+b are squares
4. Let a, b, c be integers.
(a) Prove if gcd(ab, c) = 1, then gcd(a,...
4. Let a, b, c be integers.
(a) Prove if gcd(ab, c) = 1, then gcd(a, c) = 1 and gcd(b, c) =
1. (Hint: use the GCD characterization theorem.)
(b) Prove if gcd(a, c) = 1 and gcd(b, c) = 1, then gcd(ab, c) =
1. (Hint: you can use the GCD characterization theorem again but
you may need to multiply equations.)
(c) You have now proved that “gcd(a, c) = 1 and gcd(b, c) = 1 if
and...
Prove: If (a,b,c) is a primitive Pythagorean triple, then either
a or b is divisible by...
Prove: If (a,b,c) is a primitive Pythagorean triple, then either
a or b is divisible by 3.
1. Prove that an integer a is divisible by 5 if and only if a2
is...
1. Prove that an integer a is divisible by 5 if and only if a2
is divisible by 5.
2. Deduce that 98765432 is not a perfect square. Hint: You can use
any theorem/proposition or whatever was proved in class.
3. Prove that for all integers n,a,b and c, if n | (a−b) and n |
(b−c) then n | (a−c).
4. Prove that for any two consecutive integers, n and n + 1 we
have that gcd(n,n + 1)...
Let (a, b, c, d) be elements within N+ (all positive natural
numbers). If a is...
Let (a, b, c, d) be elements within N+ (all positive natural
numbers). If a is less than/equal to b, and c is less than/equal to
d, then (a*c) is less than/equal to (b*d) with equality if and only
if a=b and c=d.
Proof?
Consider the ring R = Z∞ = {(a1,a2,a3,···) : ai ∈ Z for all
i}.
It...
Consider the ring R = Z∞ = {(a1,a2,a3,···) : ai ∈ Z for all
i}.
It turns out that R forms a ring under the operations:
(a1,a2,a3,···)+(b1,b2,b3,···)=(a1 +b1,a2 +b2,a3 +b3,···),
(a1,a2,a3,···)·(b1,b2,b3,···)=(a1 ·b1,a2 ·b2,a3 ·b3,···)
Let I = {(a1,a2,a3,···) ∈ Z∞ : all but finitely many ai are 0}.
You may use without proof the fact that I forms an ideal of R.
a) Is I principal in R? Prove your claim.
b) Is I prime in R? Prove your claim....
Consider the ring R = Z∞ = {(a1,a2,a3,···) : ai ∈ Z for all
i}.
It...
Consider the ring R = Z∞ = {(a1,a2,a3,···) : ai ∈ Z for all
i}.
It turns out that R forms a ring under the operations:
(a1,a2,a3,···)+(b1,b2,b3,···)=(a1 +b1,a2 +b2,a3 +b3,···),
(a1,a2,a3,···)·(b1,b2,b3,···)=(a1 ·b1,a2 ·b2,a3 ·b3,···)
Let I = {(a1,a2,a3,···) ∈ Z∞ : all but finitely many ai are 0}.
You may use without proof the fact that I forms an ideal of R.
a) Is I principal in R? Prove your claim.
b) Is I prime in R? Prove your claim....