Question

Find the value of A, if cos(3A-10) = sin(A-20)

Answer 1

Answer:

A= 30°.

Step-by-step explanation:

Refer to the attachment...

Answer 2

The value of A is "30°".

Step-by-step explanation:

We have,

$\cos\ (3A - 10) = \sin\ (A - 20)$

⇒$\cos\ (3A - 10) = \cos\ ( \frac{\pi}{2} - (A - 20))$

⇒ 3A - 10 = $\frac{\pi}{2} - (A - 20)$

⇒ 3A - 10 = $\frac{\pi}{2} - A + 20)$

⇒ 3A + A = 90° + 20° + 10°

⇒ 4A = 120°

⇒ A = $\frac{120}{4}$ = 30°

Hence, the value of A is 30°.