Trigonometric Equations Question 188
Question: In triangle $ ABC $ , $ (b+c)\cos A+(c+a)\cos B $ $ +(a+b)\cos C= $
[MP PET 1985]
Options:
A) 0
B) 1
C) $ a+b+c $
D) $ 2(a+b+c) $
Show Answer
Answer:
Correct Answer: C
Solution:
- $ (b+c)\cos A+(c+a)\cos B+(a+b)\cos C=a+b+c $ From expanding and collecting terms using projection rule, $ a=b\cos C+c\cos B $ etc.
BETA
