TRIGONOMETRY

Ø The branch of mathematics dealing with the relations of the sides and angles of triangles and with the relevant functions of any angles.

Ø Trigonometric angles

Ø Sine(sin)

Ø Cosine(cos)

Ø Tangent(tan)

Ø Trigonometric ratios

Ø Sin

Ø Cos

Ø Tan

Ø Cosec

Ø Sec

Ø Cot

PROBLEMS

1. Prove that

Solution:

2. A tower stands vertically on the ground. From a point on the ground, which is 48 m away from the foot of the tower, the angle of elevation of the top of the tower is 30 . Find the height of the tower.

Solution:

3. From a point on the ground, the angles of elevation of the bottom and top of a tower fixed at the top of a 30 m high building are 45° and 60° respectively. Find the height of the tower.

Solution:

4. From the top of a 12 m high building, the angle of elevation of the top of a cable tower is 60° and the angle of depression of its foot is 30°. Determine the height of the tower.

Solution:

5. A pole 5 m high is fixed on the top of a tower. The angle of elevation of the top of the pole observed from a point ‘A’ on the ground is 60° and the angle of depression to the point ‘A’ from the top of the tower is 45°. Find the height of the tower.

Solution: