function
It is called a formula.
Ohm's Law
It is called a recipe. The mathematical analogy is an algorithm.
Ecological model.
There is no formula or equation for playing chess. It's called "skills" and "ability".
In mathematical terms it's called a rhombus.
Ecological model
depending on the grade of the formula they can be called lines - 1st degree -, hyperbole - 2nd degree -, ... generally speaking all of them are called splines.
A mathematical rule can be called many things including a theory. Proofs can prove this theory to be a rule.
If built-in it is a function. If the user types it into a cell, it is a formula.
If built-in it is a function. If the user types it into a cell, it is a formula.
If built-in it is a function. If the user types it into a cell, it is a formula.