A) \[{{a}^{2}}+{{b}^{2}}-{{c}^{2}}\]
B) \[{{c}^{2}}+{{a}^{2}}-{{b}^{2}}\]
C) \[{{b}^{2}}-{{c}^{2}}-{{a}^{2}}\]
D) \[{{c}^{2}}-{{a}^{2}}-{{b}^{2}}\]
Correct Answer: B
Solution :
\[2ac\,\,\sin \frac{A-B+C}{2}=2ac\,\,\sin \frac{\pi -2B}{2}=2ac\,\,\cos B\]= \[2ac\,\frac{{{c}^{2}}+{{a}^{2}}-{{b}^{2}}}{2ca}={{c}^{2}}+{{a}^{2}}-{{b}^{2}}\].
You need to login to perform this action.
You will be redirected in
3 sec
