[Math] Calculus and Vectors Question

[w00t22]

I'm back with another question.

Determine the angle between p, q if (p - 2q) is perpendicular to (p + 6q) and |p| = 3|q|. 
q and p are vectors didn't know how to put arrow above them.

Thanks for any help in advance.

 

[enouwee]

(1) a  x + b  y + c  = 0
(2) a' x + b' y + c' = 0

Both are perpendicular if (1) and (2):

a a' + b b' = 0

Fill in your vector values and you're done and next time do your homework yourself.

 

[Zakyath]

[Slightly off topic]

Asking for help doesn't necessarily mean you are not doing your homework; it might just mean you're not understanding what stands in the book, or that one specific question uses some extra method that is not explained.

 

[w00t22]

Fill in your vector values and you're done and next time do your homework yourself.

first off this is a TIPS question and my whole class has had a problem with it since we have never done anything like this before, only get value and solve for it.