The formula of Founder Fit needs to enter the mathematical state and be edited when it is imported into the book version. A formula is a formula that uses mathematical symbols to express a certain relationship (such as a law or theorem) between various quantities. It is universal and applicable to all similar problems. In mathematical logic, a formula is a formal grammatical object to express a proposition, but the proposition may depend on the free variable value of the formula. The exact definition of a formula depends on the specific formal logic involved, but there is a very typical definition (for first-order logic): a formula is defined relative to a specific language. That is, a set of constant symbols, function symbols and relational symbols, in which each function and relational symbol has an arity to indicate the number of parameters it accepts.