Question

solve asap
maths
trignometry

Answer 1

you can see your answer

Answer 2

2cos²(A/2) = 1
cos²(A/2) = 1/2
cos(A/2) = 1/√2
cos(A/2) = cos45°
A/2 = 45°
A = 90°

Therefore, $A=90°$