Question

if Sin A = 1÷5 and π÷2 <A<π, Find Cos A​

Answer 1

Step-by-step explanation:

where sinA=1/5 then square on both sides

sin^2A=1/25

1-cos^2A=1/25

1-1/25=cos^2A

25-1/25=cos^2A

24/25=co^2A

cosA=√24/√25

cosA=2√6/5