यदि \( A + B + C = \pi^c \) भए प्रमाणित गर्नुहोस् : If \( A + B + C = \pi^c \) then prove that: \( \cos A + \cos B - \cos C =…
SEE Class 10 Optional Maths · 2081 · Solved Question with Answer
यदि \( A + B + C = \pi^c \) भए प्रमाणित गर्नुहोस् :
If \( A + B + C = \pi^c \) then prove that:
\( \cos A + \cos B - \cos C = 4\cos\dfrac{A}{2}.\cos\dfrac{B}{2}.\sin\dfrac{C}{2} - 1 \)