src/HOL/Nonstandard_Analysis/HLog.thy
changeset 80521 5c691b178e08
parent 70723 4e39d87c9737
child 80528 6dec6b1f31f5
equal deleted inserted replaced
80520:b0d590e75592 80521:5c691b178e08
    71 
    71 
    72 lemma hlog_powhr_cancel [simp]: "\<And>a y. 0 < a \<Longrightarrow> a \<noteq> 1 \<Longrightarrow> hlog a (a powhr y) = y"
    72 lemma hlog_powhr_cancel [simp]: "\<And>a y. 0 < a \<Longrightarrow> a \<noteq> 1 \<Longrightarrow> hlog a (a powhr y) = y"
    73   by transfer simp
    73   by transfer simp
    74 
    74 
    75 lemma hlog_mult:
    75 lemma hlog_mult:
    76   "\<And>a x y. 0 < a \<Longrightarrow> a \<noteq> 1 \<Longrightarrow> 0 < x \<Longrightarrow> 0 < y \<Longrightarrow> hlog a (x * y) = hlog a x + hlog a y"
    76   "\<And>a x y. 0 < a \<Longrightarrow> a \<noteq> 1 \<Longrightarrow> (x\<noteq>0 \<longleftrightarrow> y\<noteq>0) \<Longrightarrow> hlog a (x * y) = hlog a x + hlog a y"
    77   by transfer (rule log_mult)
    77   by transfer (rule log_mult)
    78 
    78 
    79 lemma hlog_as_starfun: "\<And>a x. 0 < a \<Longrightarrow> a \<noteq> 1 \<Longrightarrow> hlog a x = ( *f* ln) x / ( *f* ln) a"
    79 lemma hlog_as_starfun: "\<And>a x. 0 < a \<Longrightarrow> a \<noteq> 1 \<Longrightarrow> hlog a x = ( *f* ln) x / ( *f* ln) a"
    80   by transfer (simp add: log_def)
    80   by transfer (simp add: log_def)
    81 
    81