Chapter 8 Class 10 Introduction to Trignometry
Concept wise

We will learn what sin, cos and tan are and how to find it.

## SOHCAHTOA

View the video in Hindi.

To see the video in English, please check our youtube channel  https://www.youtube.com/watch?v=98XBc1IlYrY&feature=youtu.be

### Transcript

Sin, Cos, Tan – SOH CAH TOA In right triangle ABC sin = Side opposite to angle theta / Hypotenuse cos = Side adjacent to angle theta / Hypotenuse tan = Side opposite to angle theta / Side adjacent to angle theta For cot, sec & cosec cosec = 1/ sin sec = 1/cos cot = 1/tan Example Find value of sin, cos, tan, cosec, cot, sec Given a triangle with sides 3, 4, 5 Here, Opposite side = 4 Adjacent Side = 3 Hypotenuse = 5 So, our values are sin = Side opposite to angle theta / Hypotenuse = 4/5 cos = Side adjacent to angle theta / Hypotenuse = 3/5 tan = Side opposite to angle theta / Side adjacent to angle theta = 4/3 For cot, sec & cosec cosec = 1/ sin = 5/4 sec = 1/cos = 5/3 cot = 1/tan = 3/4 To learn the formulas, we use SOH CAH TOA SOH = sin equals opposite by Hypotenuse sin = Opposite/Hypotenuse CAH = cos equal adjacent by hypotenuse cos = Adjacent/Hypotenuse TOA = tan equals opposite by adjacent tan = Opposite/Adjacent

Made by

#### Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.