InterviewSolution
 Saved Bookmarks
    				| 1. | 
                                    In a triangle `ABC` if `cot(A/2)cot(B/2)=c, cot(B/2)cot(C/2)=a ` and `cot(C/2)cot(A/2)=b` then `1/(s-a)+1/(s-b)+1/(s-c)=`A. `-1`B. 0C. 1D. 2 | 
                            
| 
                                   
Answer» Correct Answer - D `cot.(A)/(2)cot.(B)/(2)=sqrt((s(s-a))/((s-b)(s-c))xx(s(s-b))/((s-c)(s-a)))=c` `rArr (s)/(s-c)=c rArr (1)/(s-c)=(c )/(s)` Similarly `(1)/(s-a)=(a)/(s),(1)/(s-b)=(b)/(s)` `rArr (1)/(s-a)+(1)/(s-b)+(1)/(s-c)=(a+b+c)/(s)=(2s)/(s)=2`  | 
                            |