Description: Distribution of division over addition. (Contributed by NM, 31-Jul-2004) (Proof shortened by Mario Carneiro, 27-May-2016)
Ref | Expression | ||
---|---|---|---|
Assertion | divdir | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | simp1 | |
|
2 | simp2 | |
|
3 | reccl | |
|
4 | 3 | 3ad2ant3 | |
5 | 1 2 4 | adddird | |
6 | 1 2 | addcld | |
7 | simp3l | |
|
8 | simp3r | |
|
9 | divrec | |
|
10 | 6 7 8 9 | syl3anc | |
11 | divrec | |
|
12 | 1 7 8 11 | syl3anc | |
13 | divrec | |
|
14 | 2 7 8 13 | syl3anc | |
15 | 12 14 | oveq12d | |
16 | 5 10 15 | 3eqtr4d | |