Metamath Proof Explorer


Theorem ltaddpr2

Description: The sum of two positive reals is greater than one of them. (Contributed by NM, 13-May-1996) (New usage is discouraged.)

Ref Expression
Assertion ltaddpr2
|- ( C e. P. -> ( ( A +P. B ) = C -> A 


Proof

Step Hyp Ref Expression
1 eleq1
 |-  ( ( A +P. B ) = C -> ( ( A +P. B ) e. P. <-> C e. P. ) )
2 dmplp
 |-  dom +P. = ( P. X. P. )
3 0npr
 |-  -. (/) e. P.
4 2 3 ndmovrcl
 |-  ( ( A +P. B ) e. P. -> ( A e. P. /\ B e. P. ) )
5 1 4 syl6bir
 |-  ( ( A +P. B ) = C -> ( C e. P. -> ( A e. P. /\ B e. P. ) ) )
6 ltaddpr
 |-  ( ( A e. P. /\ B e. P. ) -> A 

7 breq2
 |-  ( ( A +P. B ) = C -> ( A 

A

8 6 7 syl5ib
 |-  ( ( A +P. B ) = C -> ( ( A e. P. /\ B e. P. ) -> A 

9 5 8 syldc
 |-  ( C e. P. -> ( ( A +P. B ) = C -> A