DanInKtown

For the record, I'll answer my own question:

let: ε = the base of natural logarithyms.

Let: j = squareroot[-1]

Euler's formula [see: http://en.wikipedia.org/wiki/Euler's_formula ] says:

ε^(jx) = cosx + jsinx

Therefore two vectors:

A(cosφ + jsinφ) = A*ε^(jφ)

B(cosψ + jsinψ) = B*ε^(jψ)

so for multiplication:

[A(cosφ + jsinφ)]*[B(cosψ + jsinψ)]

= [A*ε^(jφ)]*[B*ε^(jψ)] = (A*B)*ε^(jφ+jψ)

= (A*B)*ε^j(φ+ψ)

by Euler's rule you can expand that to

(A*B)*[cos(φ+ψ) + jsin(φ+ψ)]

and for division:

[A(cosφ + jsinφ)]/[B(cosψ + jsinψ)]

= [A*ε^(jφ)]/[B*ε^(jψ)] = (A/B)*ε^(jφ-jψ)

= (A/B)*ε^j(φ-ψ)

by Euler's rule you can expand that to

(A/B)*[cos(φ-ψ) + jsin(φ-ψ)]

And that's the basis for what I was taught (and you may have learned) by rote:

When multiplying vectors you add their angles.

When dividing vectors subtact the angle of the denominator from the angle of the numerator.

It's really as simple as Advanced Algebra. :)

My reply doesn't appear in my Yahoo Mail Sent folder, although ordinary Yahoo Mail I send does.

For instance when I go to http://www.cbc.ca/player/Radio/ and select "The Sunday Edition" (down on the left near the bottom) any segment I try to play yields "the selected item is not currently available" in CBC's on-screen player. I've tried this with the following browsers:Firefox, Chrome, Opera; it just doesn't work.

On the other hand, I have no trouble LISTENing LIVE to anything available near the top of the page.

I'm trying to get my cable TV provider to fix errors in their ON SCREEN guide listing.

Who is your cable TV provider?

What does your provider's ON SCREEN guide list on QVC at 1 PM EST today?

Name of show _____________

Length of show ____________ [for example 1:00 PM to 4:00 PM]

Thank you.