Example 8 If 7 cos A - 24 sin A = 0 and A being in the Ist Quadrant. Find the values of tan A, sec A and csc A.

Solution: 7 cos A - 24 sin A= 0

Example 9

Solution:

TYPE II

Example 1 Find the value of

Solution

Example 2 Prove that

Solution : cot (90⁰ - A) = tan A,

csc (90⁰ - A) = sec A     ... [ cofunction relations]

\ cot (90⁰ - a) + csc (90⁰ - A) = tan A + sec A

EXAMPLE 3

Solution: csc (90⁰ - ) = sec , sin (90⁰ - ) = cos
....[cofunction relations]

and tan (90⁰ - ) = cot

Example 4

Solution:

Example 5 Find the value of

Solution:

\ A is in II Quadrant and IV Quadrant (by ASTC)

    \ csc A = 5/4

Thus we have

Therefore,

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Index

Trignometric Identities

4.1 Fundamental Identities
4.2 The addition formulas
4.3 The multiple-angle (Double & Half angle) formulas
4.4 Tangent Identities
4.5 Factorization & Defactorization

Supplementary Problems