Metamath Proof Explorer


Theorem pntrf

Description: Functionality of the residual. Lemma for pnt . (Contributed by Mario Carneiro, 8-Apr-2016)

Ref Expression
Hypothesis pntrval.r
|- R = ( a e. RR+ |-> ( ( psi ` a ) - a ) )
Assertion pntrf
|- R : RR+ --> RR

Proof

Step Hyp Ref Expression
1 pntrval.r
 |-  R = ( a e. RR+ |-> ( ( psi ` a ) - a ) )
2 rpre
 |-  ( a e. RR+ -> a e. RR )
3 chpcl
 |-  ( a e. RR -> ( psi ` a ) e. RR )
4 2 3 syl
 |-  ( a e. RR+ -> ( psi ` a ) e. RR )
5 4 2 resubcld
 |-  ( a e. RR+ -> ( ( psi ` a ) - a ) e. RR )
6 1 5 fmpti
 |-  R : RR+ --> RR