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A triple product 2016-10-03
From sam:
Let a and b are vectors such that
Vector a = (1,1,2)
Vector b = (2,-1,1)
And let vector c be a unit vector such that triple product of a,b,c is minimum . We have to find the value of c.

I thought triple product of a b, c means the volume occupied by parallelepiped. And we have to do volume minimum

Answered by Penny Nom.
Slicing a rectangular parallelepiped 2011-02-23
From tom:
a) Pass a plane containing a vertex of a rectangular parallelepiped and a diagonal of a face not containing that vertex to cut a pyramid from the parallelepiped. What fraction of the volume of the parallelepiped is the volume of the pyramid thus cut off?

b)Pass a plane through a cube of edge 8 in so that the section formed will be a regular hexagon. Through each side of the hexagon pass two planes, one plane containing one of the two vertices of the cube which are farthest away from the plane of the hexagon, the other plane containing the diagonally opposite vertex of the cube. Find the volume of the solid bounded by these planes.

c)three of the edges of a rectangular parallelepiped that meet in a point are also the lateral edges of a pyramid. What fraction of the parallelepiped is this pyramid...?

you know the my only problem is how to illustrate this one...if only i could ...can you help me....all I need is the drawing and I can do the rest ..it's fine if you'll only answer any of these but I'll be thankful if you will do the three :)....

Answered by Penny Nom.
Area and volume of a parallelepiped 2010-12-14
From ryan:
Got a question, I'm really confused what the question mean and how the diagram would look like... someone please help... Here's the question.

The base of a parallelepiped is a rectangle 4m by 6m. If its lateral edge is 8m and is inclined at an angle 45 degrees to a 6m edge of the base, find the total area and volume of its parallelepiped.

My dilemma is what does it mean by the lateral edge of 8m is inclined at 45 degrees to a 6m edge of the base? Can someone post a diagram to help me solve the promble. Thanks in advance.

Answered by Chris Fisher.
A parallelepiped 2004-09-25
From Aman:
" If OA, OB, and OC are three edges of a parallelepiped where O is (0,0,0), A is (2,4,-2), B is (3,6,1), and C is (4,0,-1), find the coordinates of the other vertices of the parallelepiped.)"
Answered by Penny Nom.
What is the name of a 3D rectangle? 2004-06-07
From Jack:
if a cube is a 3D square, what is the name of a 3D rectangle?
Answered by Penny Nom.



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