TrigIdentity
Intermediate
Show that $\sin\alpha + \sin\beta + \sin\gamma - \sin(\alpha + \beta+\gamma) = 4\sin\frac{\alpha+\beta}{2}\sin\frac{\beta+\gamma}{2}\sin\frac{\gamma+\alpha}{2}$
The solution for this problem is available for
$0.99.
You can also purchase a pass for all available solutions for
$99.