Question

if sin5A=cos4A, where 5A and 4A are acute angles, find the value of A?

Answer 1

sin 5A =cos 4A

we know sin (90-@) =cos@
use this
sin 5A = sin (90-4A)
5A = 90 -4A
9A = 90
A= 10

Answer 2

according to the question :

sin a = cos(90-a)

sin 5a= cos 4a

so, sin 5a = cos ( 90 - 4a) 

5a = ( 90 - 4a )

5a + 4a = 90

9a = 90 

so,   a = 10

the value of a = 10 hope it will help is so thn plzz mark it as a brainleist one ^_^