સરવાળો $S = \sin \theta + \sin 2\theta + \dots + \sin n\theta$ બરાબર શું થાય?

• A
  $\frac{\sin \frac{1}{2}(n + 1)\theta \sin \frac{1}{2}n\theta}{\sin \frac{\theta}{2}}$
• B
  $\frac{\cos \frac{1}{2}(n + 1)\theta \sin \frac{1}{2}n\theta}{\sin \frac{\theta}{2}}$
• C
  $\frac{\sin \frac{1}{2}(n + 1)\theta \cos \frac{1}{2}n\theta}{\sin \frac{\theta}{2}}$
• D
  $\frac{\cos \frac{1}{2}(n + 1)\theta \cos \frac{1}{2}n\theta}{\sin \frac{\theta}{2}}$