Question

Ex1 c) va roog
Dau coroana

Answer 1

X ∈ M₂ ⇒ $\left[\begin{array}{ccc}m&n\\an&m+bn\end{array}\right]$

A · X =  $\left[\begin{array}{ccc}an&m+bn\\a(m+bn)&an+b(m+bn)\end{array}\right]$, m, n ∈ Z (1)

X · A = $\left[\begin{array}{ccc}an&m+bn\\a(m+bn)&an+b(m+bn)\end{array}\right]$ , m, n ∈ Z (2)

Din (1) si (2) ⇒ A ·X = X·A, m,n ∈ Z.