How are P and ((z1*s2 - z2*s1)/(r*(s1-s2))) calculated? Given:

p  = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141
r  = 0xd47ce4c025c35ec440bc81d99834a624875161a26bf56ef7fdc0f5d52f843ad1
s1 = 0x44e1ff2dfd8102cf7a47c21d5c9fd5701610d04953c6836596b4fe9dd2f53e3e
s2 = 0x9a5f1c75e461d7ceb1cf3cab9013eb2dc85b6d0da8c3c6e27e3a5a5b3faa5bab
z1 = 0xc0e2d0a89a348de88fda08211c70d1d7e52ccef2eb9459911bf977d587784c6e
z2 = 0x17b0f41c8c337ac1e18c98759e83a8cccbc368dd9d89e5f03cb633c265fd0ddc


How is "P" calculated?
Which calculator/script is used to calculate z1*s2, in here ((z1*s2 - z2*s1)/(r*(s1-s2))) and so on????

Thanks so much, I will appreciate your clarification.
How is "P" calculated?


P is one of the parameters for the secp256k1 curve as defined in http://www.secg.org/sec2-v2.pdf.


  Which calculator/script is used to calculate z1*s2, in here ((z1*s2 - z2*s1)/(r*(s1-s2))) and so on????


Any calculator you want. They are just integers (albeit large integers) so you can use anything that can do large integer computations.