List of top Mathematics Questions on Various Forms of the Equation of a Line asked in Kerala Engineering Agricultural Medical Entrance Examination

Simplify the following expression: cos⁡18∘cos⁡42∘cos⁡78∘. \cos 18^\circ \cos 42^\circ \cos 78^\circ. The simplified form is:
Simplify the following expression: sin⁡7x+sin⁡5xcos⁡7x+cos⁡5x \frac{\sin 7x + \sin 5x}{\cos 7x + \cos 5x} The simplified form is:
Evaluate the sum ∑n=124(in+in+1) \sum_{n=1}^{24} \left( i^n + i^{n+1} \right) is: