Metamath Proof Explorer


Theorem bramul

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

Ref Expression
Assertion bramul A B C bra A B C = B bra A C

Proof

Step Hyp Ref Expression
1 ax-his3 B C A B C ih A = B C ih A
2 1 3comr A B C B C ih A = B C ih A
3 hvmulcl 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 C bra A C = C ih A
8 7 3adant2 A B C bra A C = C ih A
9 8 oveq2d A B C B bra A C = B C ih A
10 2 6 9 3eqtr4d A B C bra A B C = B bra A C