Trigonometric Equations Question 186
Question: In a $ \Delta ABC $ , if $ 2s=a+b+c $ and $ (s-b)(s-c)= $ $ x{{\sin }^{2}}\frac{A}{2}, $ then x =
[MP PET 1992]
Options:
A) bc
B) ca
C) ab
D) abc
Show Answer
Answer:
Correct Answer: A
Solution:
- $ \sin \frac{A}{2}=\sqrt{\frac{(s-b)(s-c)}{bc}} $
$ \Rightarrow bc{{\sin }^{2}}\frac{A}{2}=(s-b)(s-c) $ Hence $ x=bc $ .
BETA
