If `A + B + C = pi` and `sum cosA cosecB cosecC = k` , then k is

If A+B+C= pi and cosA cosecB cosecC + cosB cosecA cosecC + cosC cosecA cosecB = s and 1+ cot 81^@ + cot 54^@ + cot 81^@ cot54^@ = p, then

If A+B+C=pi and cosA=cosBcosC , then tanBtanC is equal to

Let A=pi/7, B =(2pi)/7, C=(4pi)/7 and cosA cos B cosC=-1//8 , then sum tan A tan B =

In a triangle ABC cosA+cosB+cosC<=k then k=

In a triangle ABC cosA+cosB+cosC<=k then k=

in any triangle ABC, which is not right angled Sigma cosA.cosecB.cosecC is equal to

If A+B+C=pi and cosA=cosB.cosC show that tanB+tanC=tanA

If A+B+C=pi . Then prove that cosA=-cos(B+C)

If A+B+C=pi , prove that : sinA cosB cosC +sinB cosC cosA + sinC cosA cosB = sinA sinB sinC .