That's okay Marcos. I had to search for quite a while to find those formulae. It would have taken longer to find my course material from the UBC course I took on the Mathematics of Finance back in the early seventies though and then have to figure out a way to post it.
I watched with some small interest in the big lie that our large Assurance companies used to become Insurance companies. When the policy holders owned them, there was no good way for the executives to give themselves gigantic bonuses. They also couldn't bribe the politicians for laws to allow them to merge with other financial institutions like the banks had done to take over the brokerage firms and trust companies. That's not to mention the kickbacks for those types of mergers and acquisitions.