Introduction of trigonometry of class 1o ncert is very tough for me please help me to solve the exercise 8.3 of question no.5 ,how i solve this question easily and give me the best trick to solve this question. If sec 4A = cosec (A – 20°), where 4A is an acute angle, find the value of A.

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sec 4A = cosec (A – 20°)

We know that sec 4A = cosec (90° – 4A)

To find the value of A, substitute the above equation in the given problem

cosec (90° – 4A) = cosec (A – 20°)

Now, equate the angles

90° – 4A= A- 20°

110° = 5A

A = 110°/ 5 = 22°

Therefore, the value of A = 22°