Vinod Singh and Shweta Pawar Solutions for Chapter: Factorization Formulae, Exercise 1: Classical Thinking

The value of $\sin 10°\sin 30°\sin 50°\sin 70°$ is equal to

The value of $\cos 20°\cos 40°\cos 60°\cos 80°$ is equal to

If $A+B+C=\pi$, then $\sin \left(A+B\right)=$

In a $\Delta ABC, \mathrm{cosec}A\left(\sin B\cos C+\cos B\sin C\right)$ is equal to

If $\alpha +\beta +\gamma =\pi$, then the value of ${\sin }^2\alpha +{\sin }^2\beta -{\sin }^2\gamma$ is equal to

If $A+B+C=\pi$, then ${\cos }^{2}A+{\cos }^{2}B-{\cos }^{2}C$ is equal to

If $A+B+C=180°$ then $\tan A+\tan B+\tan C$ is equal to

If $A+B+C=\pi$ and $\cos A=\cos B\cos C$, then the value of $\cot B\cot C=$