Metamath Proof Explorer


Theorem hvsubdistr2

Description: Scalar multiplication distributive law for subtraction. (Contributed by NM, 19-May-2005) (New usage is discouraged.)

Ref Expression
Assertion hvsubdistr2 A B C A B C = A C - B C

Proof

Step Hyp Ref Expression
1 hvmulcl A C A C
2 1 3adant2 A B C A C
3 hvmulcl B C B C
4 3 3adant1 A B C B C
5 hvsubval A C B C A C - B C = A C + -1 B C
6 2 4 5 syl2anc A B C A C - B C = A C + -1 B C
7 mulm1 B -1 B = B
8 7 oveq1d B -1 B C = B C
9 8 adantr B C -1 B C = B C
10 neg1cn 1
11 ax-hvmulass 1 B C -1 B C = -1 B C
12 10 11 mp3an1 B C -1 B C = -1 B C
13 9 12 eqtr3d B C B C = -1 B C
14 13 3adant1 A B C B C = -1 B C
15 14 oveq2d A B C A C + B C = A C + -1 B C
16 negcl B B
17 ax-hvdistr2 A B C A + B C = A C + B C
18 16 17 syl3an2 A B C A + B C = A C + B C
19 negsub A B A + B = A B
20 19 3adant3 A B C A + B = A B
21 20 oveq1d A B C A + B C = A B C
22 18 21 eqtr3d A B C A C + B C = A B C
23 6 15 22 3eqtr2rd A B C A B C = A C - B C