Help to solve problem

A cube has an edge length of d. Point C is at the center of the top face of the cube. express the length of the path from vertez to vertex B to the center point C in terms of d. Use the idea that the square root of (N X N). Estimate any numerical square roots needed to the nearest tenth.

"of the path from vertez to vertex B "

Vertez is which vertex can you specify ?

Prasoon Dixit
tutor-maths