Description: Addition of a positive number increases the sum. (Contributed by Scott Fenton, 15-Apr-2025)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | sltaddpos.1 | |- ( ph -> A e. No ) |
|
| sltaddpos.2 | |- ( ph -> B e. No ) |
||
| Assertion | sltaddpos2d | |- ( ph -> ( 0s |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | sltaddpos.1 | |- ( ph -> A e. No ) |
|
| 2 | sltaddpos.2 | |- ( ph -> B e. No ) |
|
| 3 | 0sno | |- 0s e. No |
|
| 4 | 3 | a1i | |- ( ph -> 0s e. No ) |
| 5 | 4 1 2 | sltadd1d | |- ( ph -> ( 0s |
| 6 | addslid | |- ( B e. No -> ( 0s +s B ) = B ) |
|
| 7 | 2 6 | syl | |- ( ph -> ( 0s +s B ) = B ) |
| 8 | 7 | breq1d | |- ( ph -> ( ( 0s +s B ) |
| 9 | 5 8 | bitrd | |- ( ph -> ( 0s |