Question

If the position vectors of the vertices of a triangle be $6\mathbf{i} + 4\mathbf{j} + 5\mathbf{k},4\mathbf{i} + 5\mathbf{j} + 6\mathbf{k}$ and $5\mathbf{i} + 6\mathbf{j} + 4\mathbf{k},$ then the triangle is

• A. Right angled
• B. Isosceles
• C. Equilateral
• D. None of these

Answer 1

Answer: (C)

Equilateral

Answer 2

Equilateral, since each side is of length $\sqrt{6}.$