Topics/Questions discussed in this video:

00:21:17 Meaning and origin of Word Trigonometry

00:24:47 Basics of Angles: Positive angles, negative angles, vertex with animations

00:34:57 Measuring an angle

00:36:07 Basics of Degree measure, minutes and seconds

00:40:57 Basics of Radian measure with animation

00:47:57 Relation between degree measure and radian measure

01:02:47 NCERT Exercise 3.1 Question 1 (Degree to radian conversion)

Find the radian measures corresponding to the following degree measures:

(i) 25°

(ii) – 47°30′

(iii) 240°

(iv) 520°