Question
यदि $\frac{{\sin A - \sin C}}{{\cos C - \cos A}} = \cot B,$ तो $A,B,C$ हैं
$\Rightarrow$ $\frac{{2\cos \frac{{A + C}}{2}\sin \frac{{A - C}}{2}}}{{2\sin \frac{{A + C}}{2}\sin \frac{{A - C}}{2}}} = \cot B$
$ \Rightarrow \cot \frac{{(A + C)}}{2} = \cot B$
$\Rightarrow$ $B = \frac{{A + C}}{2}$
अत: $A, B, C$ समान्तर श्रेणी में होंगे।
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.