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Theorem addgt0 8776
Description: The sum of 2 positive numbers is positive. (Contributed by NM, 1-Jun-2005.) (Proof shortened by Andrew Salmon, 19-Nov-2011.)
Assertion
Ref Expression
addgt0  |-  ( ( ( A  e.  RR  /\  B  e.  RR )  /\  ( 0  < 
A  /\  0  <  B ) )  ->  0  <  ( A  +  B
) )

Proof of Theorem addgt0
StepHypRef Expression
1 00id 8467 . 2  |-  ( 0  +  0 )  =  0
2 0re 8326 . . . 4  |-  0  e.  RR
3 lt2add 8773 . . . 4  |-  ( ( ( 0  e.  RR  /\  0  e.  RR )  /\  ( A  e.  RR  /\  B  e.  RR ) )  -> 
( ( 0  < 
A  /\  0  <  B )  ->  ( 0  +  0 )  < 
( A  +  B
) ) )
42, 2, 3mpanl12 440 . . 3  |-  ( ( A  e.  RR  /\  B  e.  RR )  ->  ( ( 0  < 
A  /\  0  <  B )  ->  ( 0  +  0 )  < 
( A  +  B
) ) )
54imp 124 . 2  |-  ( ( ( A  e.  RR  /\  B  e.  RR )  /\  ( 0  < 
A  /\  0  <  B ) )  ->  (
0  +  0 )  <  ( A  +  B ) )
61, 5eqbrtrrid 4166 1  |-  ( ( ( A  e.  RR  /\  B  e.  RR )  /\  ( 0  < 
A  /\  0  <  B ) )  ->  0  <  ( A  +  B
) )
Colors of variables:    wff set class
This proof depends on syntax axioms:    -> wi 4    /\ wa 104    e. wcel 2209   class class class wbr 4130  (class class class)co 6085   RRcr 8178   0cc0 8179    + caddc 8182    < clt 8360
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 623  ax-in2 624  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-14 2212  ax-ext 2220  ax-sep 4249  ax-pow 4311  ax-pr 4346  ax-un 4578  ax-setind 4684  ax-cnex 8270  ax-resscn 8271  ax-1cn 8272  ax-1re 8273  ax-icn 8274  ax-addcl 8275  ax-addrcl 8276  ax-mulcl 8277  ax-addcom 8279  ax-addass 8281  ax-i2m1 8284  ax-0id 8287  ax-rnegex 8288  ax-pre-lttrn 8293  ax-pre-ltadd 8295
This proof depends on definitions:  df-bi 117  df-3an 1011  df-tru 1405  df-fal 1408  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ne 2421  df-nel 2516  df-ral 2533  df-rex 2534  df-rab 2537  df-v 2823  df-dif 3222  df-un 3224  df-in 3226  df-ss 3233  df-pw 3690  df-sn 3715  df-pr 3716  df-op 3718  df-uni 3936  df-br 4131  df-opab 4193  df-xp 4780  df-iota 5337  df-fv 5385  df-ov 6088  df-pnf 8362  df-mnf 8363  df-ltxr 8365
This theorem is used by:  addgt0i  8816  rpaddcl  10078
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