# Introduction

We can see that Trigonometry finds its use in our day - to - day life. It was invented to be of use in astronomy. Later it was used to calculate the distance of the Earth from the planets and stars.

It finds its use in constructing maps as well as in navigation. It is used to find the position of an island in relation to longitudes and latitudes. It was used in a surveying project to discover the highest mountain in the world called "Great Trigonometry Survey".Â

Another important practical application of trigonometry is, to find the heights of objects and the distance between them.

It is practically impossible to physically measure the height of a mountain or building, width of a river, etc. but they can be determined using trigonometric ratios. The concepts of the angle of elevationÂ and the angle of depression are useful in estimating the heights of cliffs, width of rivers, etc.

Different Applications of Trigonometry

1. Trigonometry has an enormous variety of applications. The most commonly mentioned are its uses in practical endeavors such as navigation, land surveying, building, etc.

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2. It is also used extensively in a number of academic fields, primarily mathematics, science and engineering.

# Survey and Astronomy

**Land Survey**

Land Surveyors, are the frequent users of trigonometry particularly, the tangent function. For example, they can use trigonometry to figure out the distance across a river.

They use it to find unknown distances and angles while measuring property and structures.

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Trigonometry is often used to calculate distances. Surveys often use trigonometry

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to estimate the distance to a faraway object.

**Astronomy**

Trigonometry plays a very important part in land survey. It is also extensively used by astronomers in determining the distance of the heavenly bodies like the sun and moon and stars.

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**Heavenly Bodies**

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