Metamath Proof Explorer


Definition df-plusf

Description: Define group addition function. Usually we will use +g directly instead of +f , and they have the same behavior in most cases. The main advantage of +f for any magma is that it is a guaranteed function ( mgmplusf ), while +g only has closure ( mgmcl ). (Contributed by Mario Carneiro, 14-Aug-2015)

Ref Expression
Assertion df-plusf +𝑓=gVxBaseg,yBasegx+gy

Detailed syntax breakdown

Step Hyp Ref Expression
0 cplusf class+𝑓
1 vg setvarg
2 cvv classV
3 vx setvarx
4 cbs classBase
5 1 cv setvarg
6 5 4 cfv classBaseg
7 vy setvary
8 3 cv setvarx
9 cplusg class+𝑔
10 5 9 cfv class+g
11 7 cv setvary
12 8 11 10 co classx+gy
13 3 7 6 6 12 cmpo classxBaseg,yBasegx+gy
14 1 2 13 cmpt classgVxBaseg,yBasegx+gy
15 0 14 wceq wff+𝑓=gVxBaseg,yBasegx+gy