Let H be the subset of M₂(R) consisting of all matrices of the form

for a, b ∈ R Exercise 23 of Section 2 shows that H is closed under both matrix addition and matrix multiplication.

a. Show that (C,+) is isomorphic to (H, +).

b. Show that (C,•) is isomorphic to (H, •).

(We say that H is a matrix representation of the complex numbers CC.)

Data from Exercise 23 of Section 2

Let H be the subset of M₂(R) consisting of all matrices of the form 

for a, b ∈ R. Is H closed under

Transcribed Image Text:

「a-b 6 a.