If in a `Delta ABC, cosA+ cosB + cosc =3/2.` Prove that `DeltaABC` is an equilateral triangle.

In a triangle ABC , bcosc +c cosB is:

Find the length of the side and perimeter of an equilateral triangle whose height is sqrt 3 cm . (i) Delta ABC is an " equilateral triangle" . (ii) "seg" AM bot side BC, B - M - C (iii) AM = sqrt 3 cm

In DeltaABC, bc=2b^(2)cos A+2c^(2)cos A-4bc cos^(2)A , then Delta ABC is

Find the height of an equilateral triangle having side 2a. (i) Delta ABC is an equilateral triangle. AB = 2a

If tan^3A+tan^3B+tan^3C=3tanA* tanB*tanC , then prove that triangle ABC is an equilateral triangle.

Prove that cosA+cosB+cosC=1+r/R

If in a triangle ABC, (bc)/(2 cos A) = b^(2) + c^(2) - 2bc cos A then prove that the triangle must be isosceless

In the adjacent figure, Delta ABC is right angled at C and DE bot AB . Prove that Delta ABC ~ Delta ADE and hence find the lengths of AE and DE ?

Delta ABC is an equilateral triangle. Point P is on base BC such that PC = 1/3BC , if AB = 6 cm, find AP. Delta ABC is an equilateral (ii) AB = 6 cm PC = 1/3 BC

Prove that the points (0,0) (3, sqrt(3)) and (3, -sqrt(3)) are the vertices of an equilateral triangle.