Metamath Proof Explorer


Definition df-3

Description: Define the number 3. (Contributed by NM, 27-May-1999)

Ref Expression
Assertion df-3
|- 3 = ( 2 + 1 )

Detailed syntax breakdown

Step Hyp Ref Expression
0 c3
 |-  3
1 c2
 |-  2
2 caddc
 |-  +
3 c1
 |-  1
4 1 3 2 co
 |-  ( 2 + 1 )
5 0 4 wceq
 |-  3 = ( 2 + 1 )