# HG changeset patch # User blanchet # Date 1384794285 -3600 # Node ID 215d41768e515399e1d600e519822ddccb064c88 # Parent f001ef2637d31c55eafba837eb8127c5be84b7a8 moved theorems out of LFP diff -r f001ef2637d3 -r 215d41768e51 src/HOL/Cardinals/Fun_More.thy --- a/src/HOL/Cardinals/Fun_More.thy Mon Nov 18 18:04:45 2013 +0100 +++ b/src/HOL/Cardinals/Fun_More.thy Mon Nov 18 18:04:45 2013 +0100 @@ -132,6 +132,18 @@ subsection {* Properties involving Hilbert choice *} +(*1*)lemma bij_betw_inv_into_LEFT: +assumes BIJ: "bij_betw f A A'" and SUB: "B \ A" +shows "(inv_into A f)`(f ` B) = B" +using assms unfolding bij_betw_def using inv_into_image_cancel by force + +(*1*)lemma bij_betw_inv_into_LEFT_RIGHT: +assumes BIJ: "bij_betw f A A'" and SUB: "B \ A" and + IM: "f ` B = B'" +shows "(inv_into A f) ` B' = B" +using assms bij_betw_inv_into_LEFT[of f A A' B] by fast + + subsection {* Other facts *} (*3*)lemma atLeastLessThan_injective: diff -r f001ef2637d3 -r 215d41768e51 src/HOL/Cardinals/Fun_More_LFP.thy --- a/src/HOL/Cardinals/Fun_More_LFP.thy Mon Nov 18 18:04:45 2013 +0100 +++ b/src/HOL/Cardinals/Fun_More_LFP.thy Mon Nov 18 18:04:45 2013 +0100 @@ -210,19 +210,6 @@ using assms unfolding bij_betw_def using f_inv_into_f by force -(*1*)lemma bij_betw_inv_into_LEFT: -assumes BIJ: "bij_betw f A A'" and SUB: "B \ A" -shows "(inv_into A f)`(f ` B) = B" -using assms unfolding bij_betw_def using inv_into_image_cancel by force - - -(*1*)lemma bij_betw_inv_into_LEFT_RIGHT: -assumes BIJ: "bij_betw f A A'" and SUB: "B \ A" and - IM: "f ` B = B'" -shows "(inv_into A f) ` B' = B" -using assms bij_betw_inv_into_LEFT[of f A A' B] by fast - - (*1*)lemma bij_betw_inv_into_subset: assumes BIJ: "bij_betw f A A'" and SUB: "B \ A" and IM: "f ` B = B'"