If A, B and C are interior angles of a triangle ABC, then what is \(\tan \left( \frac{B + C}{2} \right) + \sin \left( \frac{B + C}{2} \right) - \cot \left( \frac{A}{2} \right) - \cos \left( \frac{A}{2} \right)\) equal to ?
1
0
2
1/2
3
\(\sin \left( \frac{A + B + C}{4} \right)\)
4
\(\tan \left( \frac{A + B + C}{4} \right)\)