A) \[1+\cos 2A+\cos 2B+\cos 2C=0\]
B) \[1+\cos 2A+\cos 2B=0\]
C) \[1+\cos 2A+\cos 2B+\cos 2C=3\]
D) \[1+\cos 2A+\cos 2B=4\]
Correct Answer: A
Solution :
Idea Use triangle law of addition of vectors \[\therefore \]In \[\Delta ABC\]You need to login to perform this action.
You will be redirected in
3 sec