Thread: 3d math questions

I have a book with questions at the end of each chapter, but no answers(3d Math Primer for Graphics and Game Development). I was wondering if anyone here could check my answers

Code:

(dfdp)=dot for dot product
(cfcp)=cross for cross product
norm(x)=normalize vector x

I.
a)  -[3 7]  =  [-3  -7]
b)  ||[-12  5]||  =  13
c)  ||[8  -3  1/2]||  =  8.56(about)
d)  3[4  -7  0]  =  [12  -21  0]
e)  [4  5]/2  =  [2  2.5]

II.
a)  norm([12  5])  =  [12/13  5/13]
b)  norm([8  -3  1/2])  =  [100/107  -75/214  25/428](about)

III.
a)  [3  10  7] - [8  -7  4]  =  [-5  17  3]
b)  3[a  b  c] -  4[2  10  -6]  =  [3a-8  3b-40  3b-24]

IV.  Compute the distance between the pairs of points
a)  [3  10  7],[8  -7  4]  =  17.972(about)
b)  [10  6],[-14  30]  =  33.941(about)

V.
a)  I don't get this one.  [2  6] (dfdp) -38???
b)  3[-2  0  4] (dfdp) ([8  -2  3/2] + [0  9  7])  =  78  (Could someone explain the order of precedence on this one?)

VI.
a)  compute angle betweent the vectors [1  2]  and [-6  3]  =  90

VII.
Given the vectors
v=[4  3  -1], n=[sqrt(2)/2  sqrt(2)/2  0]
separate v into components that are perpendicular and parallel to n.(n is a unit vector)  I don't know how to do this one

VIII.
[3  10  7] (cfcp) [8  -7  4] =  [89  44  -101]

thanks for any help.

The answers are in the back of the book and/or on the website mentioned in the book.

Thank you very much Bubba; I don't have any answers in the back of my book, and I checked the website. Thanks for the support.