QJEEAdv05Mabf98: JEE Advanced 2005 Mathematics - Class 11 JEEAdv05Mabf98 Solution: In a triangle , are the lengths of its sides and are the angles …

Multiple Choice Options

• A $\left( {b - c} \right)\sin \left( {{{B - C} \over 2}} \right) = a\cos {A \over 2}$
• B $\left( {b - c} \right)cos\left( {{A \over 2}} \right) = a\,sin{{B - C} \over 2}$
• C $\left( {b + c} \right)\sin \left( {{{B + C} \over 2}} \right) = a\cos {A \over 2}$
• D $\left( {b - c} \right)cos\left( {{A \over 2}} \right) = 2a\,sin{{B + C} \over 2}$