What Is Trigonometry?

Trigonometry is…
i) A ration shows approximate sizes of two or more values. Ratios can be shown in different ways. For example 1:3 (one to three), ¼ (one fourth). ii)
* Sine (θ) = Opposite x Hypotunese-1
* Cosine (θ) = Adjacent x Hypotunese-1
* Tangent (θ) = Opposite x Adjacent -1
iii) You can remember this equations throughout a word SohCahToa Trigonometry came from…
i) The term “trigonometry,” although not of native Greek origin, comes from the Greek word trigonon, meaning “triangle,” and the Greek word -metria, meaning“measurement.” As the name implies, trigonometry ultimately developed from the study of right triangles by applying the relationships between the measures of its sides andangles to the study of similar triangles. However, the word “trigonometry” did not exist upon the birth of the subject, but was later introduced by the German mathematician and astronomer, Bartholomaeus Pitiscus in the title of his work, Trigonometria sive de solutione triangularum tractatus brevis et perspicius…, publishedin 1595 ii) In our days, we have a lot of use for trigonometry. We can use trigonometry in Astronomy, geography, engineering, physics and finally mathematics. Trigonometric tables were created over two thousand years ago for studying astronomy.

The stars were thought to be fixed on a crystal sphere of great size, and that model was perfect for practical purposes. Only the planets moved on the sphere. The kind of trigonometry needed to understand positions on a sphere is called spherical trigonometry. Spherical trigonometry is rarely taught now since its job has been taken over by linear algebra. However, one of application of trigonometry is astronomy. Physics lays heavy demands on trigonometry. Optics and statics are two early fields of physics that use trigonometry, but all branches of physics use trigonometry since trigonometry aids in understanding space. Related fields such as physical chemistry naturally use trigonometry. Of course, trigonometry is used throughout mathematics, and, since mathematics is applied throughout the natural and social sciences, trigonometry has many applications. Calculus, linear algebra, and statistics, in particular, use trigonometry and have many applications in the all the sciences. iii)

iv) Hipparchus was called the father of trigonometry. Hipparchus was a Greek mathematician that lived in the second century BCE. He was said to use Hellenistic mathematics to create his theory of trigonometry. v) Trigonometry is a branch of mathematics that studies triangles and the relationships between their sides and the angles between these sides. Trigonometry means the trigonometric functions, which describe those relationships and have applicability to cyclical phenomena, such as waves.

How do we use trigonometry?
i) C2 = B2 + A2 – 2 x B x A x cos C ‍‍–> 13 x 13 = 12 x 12 + 5 x 5 – 2 x 12 x 5 x cos A –> 169 = 144 + 25 – 120 x cos A –> 169 – 169 = – 120 x cos A –> (169 – 169) / 120 = cos A –> A = cos -1 [(169 – 169) / 120] –> A = 90˚ ii) Soh Cah Toa –> Sine (θ) = Opposite x Hypotunese-1 –> Sin (59) = X x 10-1 –> X = 10 x Sin (59) –> X = 8.57 iii)