Question

5. If sec 4A = cosec (A - 20°), where 4A is an acute angle, find the value of A.
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Answer 1

Answer:

A = 22°

Step-by-step explanation:

Sec 4A = cosec ( A - 20°)

=> Cosec ( 90° - 4A) = cosec ( A - 20° )

[ sec A = cosec ( 90° - A )]

=> 90° - 4A = A - 20°

=> 90° + 20° = A + 4A

=> 110° = 5A

=> A = 110° / 5

Therefore , A = 22°

Answer 2

$\sec(4a) = \cosec(a - 20) \\ \\ \cosec(90 - 4a) = \cosec(a - 20) \\ \\ (90 - 4a) = (a - 20) \\ \\ 90 + 20 = a - 4a \\ \\ 5a = 110 \\ \\ a = \frac{110}{5} \\ \\ a = 22 \: answer \\ \\ \\ {\huge{\boxed{\mathbb{\purple{Stay \: strong}}}}}$