Trigonometric Equations Question 273
Question: In a $ \Delta ABC,\frac{\cos C+\cos A}{c+a}+\frac{\cos B}{b} $ is equal to
[EAMCET 2001]
Options:
A) $ \frac{1}{a} $
B) $ \frac{1}{b} $
C) $ \frac{1}{c} $
D) $ \frac{c+a}{b} $
Show Answer
Answer:
Correct Answer: B
Solution:
- $ \frac{\cos C+\cos A}{c+a}+\frac{\cos B}{b} $ $ =\frac{(b\cos C+c\cos B)+(b\cos A+a\cos B)}{b(c+a)} $ $ =\frac{a+c}{b(c+a)} $ , (using Projection formulae) $ =\frac{1}{b} $ .
BETA
