Tutorial Sheet 3: Algebraic Structures


 

 

Exercise 3

Let (G, *) be a group with neutral element e such that:

∀x ∈ G, x * x = e.

Show that * is commutative.

Exercise 4

Consider the groups (ℝ, +) and (ℝ*+, ⋅). We define the mapping:

f : ℝ → ℝ*+ defined by ∀x ∈ ℝ, f(x) = 4^x.

Show that f is a group isomorphism.

Last modified: Friday, 5 September 2025, 1:19 PM