Explanation: 
Another Explanation (5):
sin(A-30°) + sin(A+150°) = ?
আমরা জানি, sin(C) + sin(D) = 2sin((C+D)/2)cos((C-D)/2) 🤓
এখানে, C = A-30° এবং D = A+150°
তাহলে,
sin(A-30°) + sin(A+150°)
= 2sin(((A-30°) + (A+150°))/2)cos(((A-30°) - (A+150°))/2) 🥳
= 2sin((2A+120°)/2)cos((-180°)/2)
= 2sin(A+60°)cos(-90°) 😎
যেহেতু cos(-90°) = 0, সুতরাং 🧐
2sin(A+60°)cos(-90°) = 2sin(A+60°) * 0 = 0
অতএব, sin(A-30°) + sin(A+150°) = 0 🥰
