Hello,

We have a not empty set X and call P(X) the power set of X. For the subsets A,B in X we define the symetric difference:

To proof:

1.)

Proof that the triple is a Ring

2.)

Is P(x) with this ringstructure a field?

3.) Proof that P(X) is a Vector Space over the Galois-field.

I have no idea

The first questions:

What is Delta?

Why is in the triple the intersection and not the union like in the definition?

How should I start?

Thanks for help

all the best

Herbststurm