Only when they are trying to calculate strength, speed, torque, power, energy consumption, temperature, which materials to use and in what amounts; other than that... I'm sure there are other times as well.
If you mean the engineer of a train, then not much. If, however, you mean the people who design and build things, then everything. Math is the most important tool for engineers, no matter what their field.
Almost all engineers use math in some form in their work. As an electrical engineer I used math to determine the values of parts like resistors and capacitors in radio circuits I designed. A mechanical engineer uses math to determine the size of parts and strength of the materials needed to build things like car engines. An aeronautical engineer uses math to design airplanes so they are safe to fly. A civil engineer uses math to determine how to place out water and sewer lines in the proper place all over the city and to design safe bridges. Math is as important a tool to an engineer as a hammer is to a carpenter.
Engineers use varying kinds of math. Such as, calculus 1,2,3, differential equations, linear algebra, probability, statistics, mathematical induction just to name a few. Anyone who majors in one of these broad engineering branches should know pre-calculus very well and be comfortable applying it.
Math is used at almost every place you can think of. Everything that happens around you can be formulated in equations. The magic of math is all around you =D
Almost every field of study requires you to know the basics of math. More advanced math is used extensively in every engineering and science field.
For programming purposes, it's when they do algorithms and game programming, otherwise, programming barely uses any mathematics at all. For non programming purposes, it depends on the profession.
Besides basic arithmetic, engineers commonly use a type of math called calculus. They also will use geometry, depending on what field of engineering they are involved with.
engineers need math because they need to use angles and measurements accurately to construct a stable object you need to be incredibly accurate or your project could tumble down
everyday they use math
Scientists will generally use their brains to solve math or other problems. Once they have established the mathematical formula to be solved, they would use a computer or (scientific) calculator to evaluate the math problem and get a solution.
i donot
Algebra
Scientists didn't like how long it took to solve math problems.
most scientists use math to find how much liquid to put into a test tube.or to find tyhe size of an animal.or to,... well, you get it, they use ALOT of math. so if you are about to be a scientist,pay attention in math and science class!
-math teachers -scientists like forensic scientists -phsycoligists
Computer programmers use math because math is a universal language. Many programmers are able to understand code when it is using numbers.
idkl
a computer
Statistics is a type of math utilized by scientists to analyze their data.
Engineers, Physicists, and literally Rocket Scientists. Oh, and of course Math Teachers. Hahah.