Re: [Hol-info] A problem of derivation

2017-11-08 Thread Liu Gengyang
t;2015200...@mail.buct.edu.cn> Cc: Subject: Re: [Hol-info] A problem of derivation Hi Liu, rewriting applies the provided equations left to write. So if if have (A = A') /\ (B = B') ==> (f A B) The simplifier (with std_ss) uses the precondition (A = A') /\ (B = B') as context and add

Re: [Hol-info] A problem of derivation

2017-11-08 Thread Liu Gengyang
Thank you very much,its works! -Original Messages- From:michael.norr...@data61.csiro.au Sent Time:2017-11-09 11:15:52 (Thursday) To: 2015200...@mail.buct.edu.cn Cc: Subject: Re: [Hol-info] A problem of derivation Use the theorem SQRT_POW_2. E.g.: Q.prove( `!a b c d.(sqrt(c pow

Re: [Hol-info] A problem of derivation

2017-11-08 Thread Thomas Tuerk
Hi Liu, rewriting applies the provided equations left to write.  So if if have (A = A') /\ (B = B') ==> (f A B) The simplifier (with std_ss) uses the precondition (A = A') /\ (B = B') as context and adds the rewrite rules A -> A' B -> B' where "->" is an ad-hoc notation for "=" but only

[Hol-info] A problem of derivation

2017-11-08 Thread Liu Gengyang
Hi, I want to prove the goal: !a b c d.(sqrt(c pow 2 + d pow 2) pow 2 = c pow 2 + d pow 2) /\ (sqrt(a pow 2 + b pow 2) pow 2 = a pow 2 + b pow 2) /\ sqrt(c pow 2 + d pow 2) pow 2 ≤ sqrt(a pow 2 + b pow 2) pow 2 ==> c pow 2 + d pow 2 ≤ a pow 2 + b pow 2 In theory this goal can be proved by