A formula or an expression.
When you perform all mathematical calculations on a problem, it is often referred to as "solving" the problem. This involves applying relevant mathematical operations and techniques to arrive at a definitive answer or conclusion. In some contexts, it may also be described as "completing" the calculations or "working through" the problem systematically.
operators
geometry
No, it is not a mathematical term.
a equation
Probability
Tactical Call Signs
The answer to the calculation is simply called the square root.
significant digits
The imperative of "Isolate the Insurgents from the Population" calls for careful calculation of the type and amount of force applied. This involves ensuring that the force applied is targeted at separating the insurgents from the population without causing excessive collateral damage or alienating the local populace.
I don't know what a 'mathematical' sentence is. I'd prefer to call it an English sentence that describes a mathematical process and makes a statement concerning mathematical matters.
This is a mathematical "expression".