Question

The figure shows a regular tetrahedron VABC with side 4 cm. M and N are the mid-points of AB and BC respectively.
(a) Find the distance between V and the line AB. Express the answer in surd form.
(b) Find the angle between the lines VM and VN.

Answer 1

@hartnn

Answer 2

regular tetrahedron VABC with side 4 cm.

regular means all the sides (edges) and faces are congruent.
that makes each face an equilateral triangle
if we focus on side VAB, they want the distance from V to the base AB