Metamath Proof Explorer


Theorem mulgcdr

Description: Reverse distribution law for the gcd operator. (Contributed by Scott Fenton, 2-Apr-2014) (Revised by Mario Carneiro, 19-Apr-2014)

Ref Expression
Assertion mulgcdr ABC0ACgcdBC=AgcdBC

Proof

Step Hyp Ref Expression
1 mulgcd C0ABCAgcdCB=CAgcdB
2 1 3coml ABC0CAgcdCB=CAgcdB
3 zcn AA
4 3 3ad2ant1 ABC0A
5 nn0cn C0C
6 5 3ad2ant3 ABC0C
7 4 6 mulcomd ABC0AC=CA
8 zcn BB
9 8 3ad2ant2 ABC0B
10 9 6 mulcomd ABC0BC=CB
11 7 10 oveq12d ABC0ACgcdBC=CAgcdCB
12 gcdcl ABAgcdB0
13 12 3adant3 ABC0AgcdB0
14 13 nn0cnd ABC0AgcdB
15 14 6 mulcomd ABC0AgcdBC=CAgcdB
16 2 11 15 3eqtr4d ABC0ACgcdBC=AgcdBC