Question

the point evaluate 5 cos (85-A)/sin (5+A)-3 sec(54-A)/cosec (36+A)

Answer 1

The answer is 2


Please refer the above photograph for the used process.



KEY POINTS TO REMEMBER :-

☸️ The trigonometric relation of complimentary angles :-

$\sin(90 - x) = \cos(x) \\ \\ \cos(90 - x) = \sin(x) \\ \\ \tan(90 - x) = \cot(x) \\ \\ \cot(90 - x) = \tan(x) \\ \\ \sec(90 - x) = \cosec(x) \\ \\ \cosec(90 - x) = \sec(x)$
Please remember them all...


☸️ COMPLIMENTARY ANGLES :- The angles whose sum is 90 degrees are known as complimentary angles.


☸️ substitution of either denominator or numerator using the complimentary relation of trigonometric ratios.


Thanks!