Answer:
Step-by-step explanation:
OB = 10 cm
OA = OC = Radius = 4 cm
COS <AB = OA/OB = 4/10 = 2/5 =
COS< COB = OC/OB = 4/10 = 2/5
=> <AOC = <AOB + <COB
=> <AOC = Cos-¹(2/5) + Cos-¹(2/5)
=> <AOC = 2 Cos-¹(2/5)
=> <AOC = 2 * 66.42
=> <AOC = 132.84°
if D is in minor arc then length of arc ADC. = ( 132.84°/360°) 2π = 9.274 cm
if D is in major arc then length of arc ADC. = ((360° -132.84°)/360°) 2π = 15.859 cm
