Please prove
1. Every positive integer is a product of prime numbers.
2. If a and b are relatively prime, and a|bc, then a|c.
3. The division algorithm for F[x]. Just the existence part
only, not the uniqueness part
Suppose V is a finite dimensional inner product space. Prove that
every orthogonal operator on V , i.e., <T(u),T(v)> =
<u,v>, ∀u,v ∈ V , is an isomorphism.
Using Kurosch's subgroup theorem for free proucts,prove that
every finite subgroup of the free product of finite groups is
isomorphic to a subgroup of some free factor.
please prove this problem step by step. thanks
Prove that in every simple graph there is a path from every vertex
of odd degree to some other vertex of odd
degree.
(1)Prove that for every a, b ∈ R, |a + b| = |a| + |b| ⇐⇒ ab ≥ 0.
Hint: Write |a + b| 2 = (|a| + |b|) 2 and expand.
(2) Prove that for every x, y, z ∈ R, |x − z| = |x − y| + |y −
z| ⇐⇒ (x ≤ y ≤ z or z ≤ y ≤ x). Hint: Use part (1) to prove part
(2).