Description: Multiplication of positive fractions is commutative. (Contributed by NM, 31-Aug-1995) (Revised by Mario Carneiro, 28-Apr-2013) (New usage is discouraged.)
Ref | Expression | ||
---|---|---|---|
Assertion | mulcomnq | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | mulcompq | |
|
2 | 1 | fveq2i | |
3 | mulpqnq | |
|
4 | mulpqnq | |
|
5 | 4 | ancoms | |
6 | 2 3 5 | 3eqtr4a | |
7 | mulnqf | |
|
8 | 7 | fdmi | |
9 | 8 | ndmovcom | |
10 | 6 9 | pm2.61i | |