$\text{If}\ \sin\alpha+\sin\beta=\text{a}\text{ and }\cos\alpha-\cos\beta=\text{b},\ \text{than }\tan\frac{\alpha-\beta}{2}=$
View full solution →- $-\frac{\text{a}}{\text{b}}$
- $-\frac{\text{b}}{\text{a}}$
- $\sqrt{\text{a}^2+\text{b}^2}$
- None of these