Metamath Proof Explorer
Description: A "decimal digit" (i.e. a nonnegative integer less than or equal to 9)
is less then 10. (Contributed by AV, 8-Sep-2021)
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|
Ref |
Expression |
|
Hypotheses |
le9lt10.c |
|
|
|
le9lt10.e |
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Assertion |
le9lt10 |
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Proof
Step |
Hyp |
Ref |
Expression |
1 |
|
le9lt10.c |
|
2 |
|
le9lt10.e |
|
3 |
1
|
nn0zi |
|
4 |
|
9nn0 |
|
5 |
4
|
nn0zi |
|
6 |
|
zleltp1 |
|
7 |
3 5 6
|
mp2an |
|
8 |
2 7
|
mpbi |
|
9 |
|
9p1e10 |
|
10 |
8 9
|
breqtri |
|