Download Study of relationships between the sides and angles of a

(Study of relationships between the sides and angles of a triangle.)
1. Trigonometric Ratios:
Ratios of the sides of a right triangle with respect to its acute angles
~ In right triangle ABC,
is an acute angle
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4. If one of the trigonometric ratios of an acute angle is known, the remaining
trigonometric ratios of the angle can be easily determined.
5. Trigonometric Ratios Of Some Specific Angles:
6. The value of sin A and cos A never exceeds 1, whereas the value of sec A or
cosec A is always greater than or equal to 1.
7. Trigonometric Ratios Of Complementary Angles:
Two angles are said to be complementary if their sum equals 90 .
𝒔𝒊𝒏 𝟗𝟎 – 𝑨
𝒔𝒊𝒏𝑩
𝒄𝒐𝒔 𝑨,
𝒄𝒐𝒔 𝟗𝟎 – 𝑨
𝒄𝒐𝒔𝑩
𝒔𝒊𝒏 𝑨,
𝒕𝒂𝒏 𝟗𝟎 – 𝑨
𝒕𝒂𝒏𝑩
𝒄𝒐𝒕 𝑨,
𝒄𝒐𝒕 𝟗𝟎 – 𝑨
𝒄𝒐𝒕𝑩
𝒕𝒂𝒏 𝑨,
𝒔𝒆𝒄 𝟗𝟎 – 𝑨
𝒔𝒆𝒄𝑩
𝒄𝒐𝒔𝒆𝒄 𝑨,
𝒄𝒐𝒔𝒆𝒄 𝟗𝟎 – 𝑨
𝒄𝒐𝒔𝒆𝒄𝑩
𝒔𝒆𝒄 𝑨.
8. Three Fundamental Trigonometric Identities:
An equation involving trigonometric ratios of an angle is called a
trigonometric identity, if it is true for all values of the angle(s) involved.
𝒔𝒊𝒏𝟐 A + 𝒄𝒐𝒔𝟐 A = 1,
𝒔𝒆𝒄𝟐 A – 𝒕𝒂𝒏𝟐 A = 1
𝒄𝒐𝒔𝒆𝒄𝟐 A = 1 + 𝒄𝒐𝒕𝟐 A