In triangle `A B C` , if `|1 1 1cotA/2cotB/2cotC/2tanB/2+tanC/2tanB/2+tanA/2tanA/2+tanB/2|` then the triangle must be a. equilateral b. isosceles c. obtuse angled`` d. none of these

In triangle ABC, if |[1,1,1], [cot (A/2), cot(B/2), cot(C/2)], [tan(B/2)+tan(C/2), tan(C/2)+ tan(A/2), tan(A/2)+ tan(B/2)]| then the triangle must be (A) Equilateral (B) Isoceless (C) Right Angle (D) none of these

In DeltaABC , prove that: tanA/2tanB/2+tanB/2tanC/2+tanC/2tanA/2=1

In any triangle ABC , (tanA/2-tanB/2)/(tanA/2+tanB/2) is equal to

In any triangle ABC if 2cos B=(a)/(c), then the triangle is(A) Right angled (C) Isosceles (B) Equilateral (D) None of these

In a triangle ABC, tanA + tanB + tanC = 9. If tan^2 A+ tan^2 B + tan^2 C= k then the least value of k^(9/7) is

In DeltaABC, if tanA+tanB+tanC=6 and tanA.tanB=2 then tanC= . .

In DeltaABC , prove that: a/(b+c)=(1-tanB/2tanC/2)/(1+tanB/2tanC/2)

If tanA=(1)/(2) and tanB=(1)/(3) , then tan(2A+B) is equal to

In DeltaABC , prove that: (b-c)/(a)=(tanB/2-tanC/2)/(tanB/2+tanC/2)