Some Applications of Trigonometry Class 10 Notes Maths Chapter 9

CBSE Class 10 Maths Notes Chapter 9 Some Applications of Trigonometry Pdf free download is part of Class 10 Maths Notes for Quick Revision. Here we have given NCERT Class 10 Maths Notes Chapter 9 Some Applications of Trigonometry. According to new CBSE Exam Pattern,Ā MCQ Questions for Class 10 Maths Carries 20 Marks. https://www.cbselabs.com/some-applications-of-trigonometry-class-10-notes/

CBSE Class 10 Maths Notes Chapter 9 Some Applications of Trigonometry

Some Applications Of Trigonometry Class 10 Notes Chapter 9

Line of Sight
When an observer looks from a point E (eye) at an object O then the straight line EO between the eye E and the object O is called the line of sight.
Some Applications of Trigonometry Class 10 Notes Maths Chapter 9 Img 1

Horizontal
When an observer looks from a point E (eye) to another point Q which is horizontal to E, then the straight line, EQ between E and Q is called the horizontal line.
Some Applications of Trigonometry Class 10 Notes Maths Chapter 9 Img 2

Applications Of Trigonometry Class 10 Notes Chapter 9

Angle of Elevation
When the eye is below the object, then the observer has to look up from the point E to the object O. The measure of this rotation (angle Īø) from the horizontal line is called the angle of elevation.
Some Applications of Trigonometry Class 10 Notes Maths Chapter 9 Img 3

Angle of Depression
When the eye is above the object, then the observer has to look down from the point E to the object. The horizontal line is now parallel to the ground. The measure of this rotation (angle Īø) from the horizontal line is called the angle of depression.
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How to convert the above figure into the right triangle.
Case I: Angle of Elevation is known
Draw OX perpendicular to EQ.
Now āˆ OXE = 90Ā°
Ī”OXE is a rt. Ī”, where
OE = hypotenuse
OX = opposite side (Perpendicular)
EX = adjacent side (Base)
Some Applications of Trigonometry Class 10 Notes Maths Chapter 9 Img 5
Case II: Angle of Depression is known
(i) Draw OQ’parallel to EQ
(ii) Draw perpendicular EX on OQ’.
(iii) Now āˆ QEO = āˆ EOX = Interior alternate angles
Ī”EXO is an rt. Ī”. where
EO = hypotenuse
OX = adjacent side (base)
EX = opposite side (Perpendicular)
Some Applications of Trigonometry Class 10 Notes Maths Chapter 9 Img 6

  • Choose a trigonometric ratio in such a way that it considers the known side and the side that you wish to calculate.
  • The eye is always considered at ground level unless the problem specifically gives the height of the observer.

The object is always considered as a point.
Some People Have
Sin Īø = \(\frac { Perpendicular }{ Hypotenuse }\)
Curly Black Hair
Cos Īø = \(\frac { Base }{ Hypotenuse }\)
Turning Permanent Black.
Tan Īø = \(\frac { Perpendicular }{ Base }\)

NCERT Solutions