# Math Is Fun Forum

Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫  π  -¹ ² ³ °

You are not logged in.

## #1 2022-05-10 04:15:30

lanxiyu
Member
Registered: 2022-05-10
Posts: 51

### Quaternions

Definition of quaternions multiplication: i^2 = j^2 = k^2 = ijk = -1
Quaternions multiplication is not commutative

Offline

## #2 2022-05-10 23:16:49

Bob
Registered: 2010-06-20
Posts: 10,546

### Re: Quaternions

hi lanxiyu

Welcome to the forum.

Is this an exercise where we should prove this or are you asking for help with it as a problem you have been set.

Either way I had better start trying to construct a proof.  Hopefully, more when (if) I succeed.

LATER EDIT. From your top line I can show at least one product is not commutative.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

Offline