Can affine functions form a group under function composition?

[POtment]

Homework Statement

Show that the set A = (f:R-->R such that f(x)=mx+b, m not= 0} of affine functions from R to R forms a group under composition of function.

The Attempt at a Solution

Obviously I need to apply the composition of functions property (f: S->T, g:T->U, g of is function from S to U defined by g(f(x)) for all x element of S), but I'm not sure how to take the first step.

 

[Vid]

Take two arbitrary elements of the group, compose them and show what you get must also be in the group.

That's one of the first steps. You need to show it satisfies all of the group axoims for the full proof.

 

[POtment]

Thanks, solved!