APT ACADEMIC SOLUTIONS …apt way of teaching : APT ACADEMIC SOLUTIONS …apt way of teaching AAS believes in people who deliver the right solutions, and it proudly possesses them.
Slide 2 : Lesson 1 TRIGONOMETRY
Session Objectives : Session Objectives Measuring Angles
Relation between degree and radian
Theorem
Trigonometric functions www.aptacads.com
Measuring Angles : Measuring Angles Two systems of measuring angles
(i) Sexagesimal system (Degree)
The angle traced by a moving line about a point is 360°
1° = 60 minute =
= 60 second = www.aptacads.com
Slide 5 : (ii) Circular System (Radian)
A radian is an angle subtended by an arc at the centre of a circle whose length is equal to radius of the circle.
1 radian can be written as 1c
Relation between Degree and Radian : Relation between Degree and Radian
Slide 7 : www.aptacads.com Some Important conversions :
Let’s do it : Let’s do it Q 1. The angles of a triangle are in AP and the greatest angle is double the least. Find all the angles in degrees and radians.
Q 2. The difference between the two acute angles of a right triangle is . Find these angles in radians and degrees. www.aptacads.com
Theorem : Theorem If an arc of length l subtends an angle ? at the centre of circle with radius r, then www.aptacads.com
Slide 10 : Q 1. Find the angle in radian through which a pendulum swings if its length is 75 cm and the tip describes an arc of length 15cm.
Slide 11 : Q 2. The large hand of a clock is 42 cm long. How many cms. does its extremity move in 20 minutes. www.aptacads.com
Trigonometric Functions : Trigonometric Functions www.aptacads.com
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Slide 14 : www.aptacads.com
Slide 15 : Thanks www.aptacads.com