Metamath Proof Explorer


Theorem braadd

Description: Linearity property of bra for addition. (Contributed by NM, 23-May-2006) (New usage is discouraged.)

Ref Expression
Assertion braadd A B C bra A B + C = bra A B + bra A C

Proof

Step Hyp Ref Expression
1 ax-his2 B C A B + C ih A = B ih A + C ih A
2 1 3comr A B C B + C ih A = B ih A + C ih A
3 hvaddcl B C B + C
4 braval A B + C bra A B + C = B + C ih A
5 3 4 sylan2 A B C bra A B + C = B + C ih A
6 5 3impb A B C bra A B + C = B + C ih A
7 braval A B bra A B = B ih A
8 7 3adant3 A B C bra A B = B ih A
9 braval A C bra A C = C ih A
10 9 3adant2 A B C bra A C = C ih A
11 8 10 oveq12d A B C bra A B + bra A C = B ih A + C ih A
12 2 6 11 3eqtr4d A B C bra A B + C = bra A B + bra A C