Compute $\sin 5^\circ + \sin 10^\circ + \sin 15^\circ + \cdots + \sin 360^\circ$
Not as difficult as it seems if we think about this
sum [ ( sin 5° + sin 10° + sin 15° + ..... + sin 180° ) + ( sin355° + sin 350° + sin 345° + .... +sin 180° ) ] = 0
And sin 0° = sin 360° = 0
Adding all these, the sum = 0
