Question

Q. 6. A)
Select and write the most appropriate alternative from those given below:
If
COS A
=1 where A is an acute angle then the value of A =
sin 72°​

Answer 1

Answer:

sin4A=cos(A−20)

Therefore,sin4A=sin(90−A+20)

sin4A=sin(110−A)

4A=110−A

A=22

Hence,∠A=22

o

Answer 2

Step-by-step explanation:

angle a will be of 69° degree