Trigonometry is not just a subject to be studied in a classroom with no real world practical applications. Engineers of various types use the fundamentals of trigonometry to build structures/systems, design bridges and solve scientific problems. Trigonometry means the study of the triangle. It is further used to find the angles of a triangle when the lengths of the sides are known, or finding the lengths of two sides when the angles and one of the side lengths are known. Once all of the measurements of the triangle (structure) are known the engineer can begin building and defining the scope of the project he or she is undertaking. The following are the steps to understanding and using Trigonometry in the field of Engineering.

Determine what field of engineering trigonometry will be used. In addition, use sound reasoning to build your business case for using trigonometry.

Define your project plans and anticipated milestones. The following are the most important questions you must ask and define in the early stages of your project development schedule. 1)What is your project scope and vision? 2)How many resources do you need? (i.e. people, supplies and inspection stations) 3)How long will this project take from start to completion? 4)How will you validate your measurements and the structural integrity of your work?

Begin taking measurements and calculating the dimensions of what you intend to build or create. For example, when studying civil engineering you will have to calculate the force distribution for different structures, such as truss bridges. The engineer must also figure out what the angles between the beams in a bridge must be, and how long they must be.

Build your structure or system according the measurements. You should also create a specification sheet for your design for future reference.

Validate the structural integrity of your work. Does it meet all of your initial requirements? Is it safe? Have you had it inspected?

#### Tip

A career that uses law of sines is aircraft maintenance and design engineer. This engineer must calculate the planes velocity as well as the air velocity in order to make it as aerodynamic as possible. Since they know the wind velocity, bearing angle and airspeed, then they can fine the angle q, which is the difference in wind direction and bearing. The use of the law of sines with wind velocity and airspeed gives the angle of offset for the aircraft. Then using the law of cosines with the third angle gives the magnitude of the resultant ground speed of the aircraft along the chosen bearing direction.

Source: “Student Essay on The Law of Sines”