TRIGONOMETRY IS EASY, BUT ONLY IF YOU STUDY THIS PDF

TRIGONOMETRY
TRIGONOMETRIC RATIOS
TRIGONOMETRY
01 04
TRICK: Some People Have
Trigonometry is the branch of mathematics in which we study the relationships Curly Brown Hair
between the sides and the angles of a triangle. To Produce Beauty. D

(H)
(P)

q
TRIGONOMETRIC RATIOS E F

02
(B)
The ratio of sides of a right angle triangle with respect to acute angles are called
"Trigonometric ratios of the angle". sin  = P/H = DE/DF
cos  = B/H = EF/DF
tan  = P/B = DE/EF

cot  = B/P = EF/DE
RIGHT ANGLE TRIANGLE
sec  = H/B = DF/EF
03
1. A triangle having one angle equal to 90º is called right angle triangle.
2. The sum of other two acute (Less than 90º) angles is 90º. (or both acute angles cosec  = H/P = DF/DE
are complementary)
3. The side opposite to 90º, is called hypotenuse, it is longest side in triangle. 1 1
4. The side opposite to given acute angle is perpendicular and side adjacent to By above table sin  = , cos 
cosec  sec 
the angle is base.
D Perp. Base 1
A C D tan 
 Hypotenuse cot 

Base




Base




Perp.
Hypo. Hypo. Points To be Remember:

E F
Perpendicular B 1. The values of sin  & cos  are always less than
or equal to 1 & greater than or equal to –1.
2. Value of tan  & cot  lie between –  to + 
A
3. sin A, cos A, etc. are not product of sin and A.
4. (sin A)2  sin A2 etc.


• sin2 = (sin )2
B C cos2 = (cos )2
Hypotenuse Perpendicular Base tan2 = (tan )2