How do i calculate this?

Posted on 2008-02-18 13:34 By EngNoob (

11)

Categories:

How do I ...? with Maple

I have been playing around with vectors, and have managed to do all the usual mathmatical things with them, except for this.

How do i figure the value for |a|

I have vectors a, b, c.

I have tried help, and google, but cant seem to find out how to find |a|

Any help appreciated, thanks.

VectorNorm or DotProduct

Comment on 2008-02-18 13:41 from John Fredsted ( Maple Rating 4

566)

You can use either VectorNorm or DotProduct as follows:

V := Vector([a,b,c]);
LinearAlgebra:-VectorNorm(V,2,conjugate = false);
sqrt(LinearAlgebra:-DotProduct(V,V,conjugate = false));

I understand that. So how do

Comment on 2008-02-18 14:45 from EngNoob (

11)

I understand that.

So how do i got a step further an calculate

a.b

a * b

I understand one is dot product and the other dot ???

Thanks for the reply

Vectors, Dot Products, Cross Products

Comment on 2008-02-19 08:37 from Tim Van Dusen ( Maple Rating 3

216)

Anyone reading this who is interested in viewing a lecture concerning vectors, and more specifically the dot products and cross products being discussed here, below is a link to a video presented by "MITOPENCOURSEWARE". The professor giving the lecture, does an extraordinary job in all the lectures provided at the site. He uses a lot of visual aids to greatly simplify the understanding of some difficult subjects.

The link: tinyurl.com/2bsnj8

DotProduct and CrossProduct

Comment on 2008-02-19 05:25 from John Fredsted ( Maple Rating 4

566)

I suppose that a * b means the cross product of the vectors a and b, something I would write as a x b. Use DotProduct (as before, but now on two different vectors, which is really what it is meant for), and CrossProduct as follows:

A := Vector([a1,a2,a3]):
B := Vector([b1,b2,b3]):
LinearAlgebra:-DotProduct(A,B,conjugate = false);
LinearAlgebra:-CrossProduct(A,B);

You may also write the cross product as

with(LinearAlgebra):
A &x B;