**TOPIC 9: TRIGONOMETRY ~ MATHEMATICS FORM 2**

Do you want to learn the relationships involving lengths and Angles of right-angled triangle? Here, is where you can learn.

**Angles of Elevation and Depression**

**Angle of Elevation **of an Object as seen by an Observer is the angle between the horizontal and the line from the Object to the Observer’s aye (the line of sight).

See the figure below for better understanding

^{}.

**Angle of depression **of an Object which is below the level of Observer is the angle between the horizontal and the Observer’s line of sight.

To have the angle of depression, an Object must be below the Observer’s level. Consider an

illustration below:

The angle of depression of the Object from the Object is β^{}

Problems involving Angles of Elevation and Angles of Depression

Solve Problems involving angles of elevation and angles of depression

**Example 5**

^{}. How far is the Object from the base of the cliff?

**Solution**

Angle of depression = 35^{}

**Exercise 1**

- cos 38.25
^{} - sin 56.5
^{} - tan 75
^{}

**2**. Use trigonometrical tables to find the value of x in the following problems.

- sin x
^{}= 0.9107 - tan x
^{}= 0.4621

**3**. Find the height of the tower if it casts a shadow of 30 m long when the angle of elevation of the sun is38^{}.

**4**. The Angle of elevation of the top of a tree of one point from east of it and 56 m away from its base is25

^{}. From another point on west of the tree the Angle of elevation of the top is50

^{}. Find the distance of the latter point from the base of the tree.

**5**. A ladder of a length 15m leans against a wall and make an angle of30^{}with a wall. How far up the wall does it reach?

Howdy! I know this is kinda off topic but I was wondering which blog platform are

you using for this site? I’m getting sick and tired of WordPress because I’ve had issues with

hackers and I’m looking at alternatives for another platform.

I would be awesome if you could point me in the direction of a good platform.

How to download the notes