   need some math help
  hello everyone i really need your help to comfirm my answers to the exercises of chapter 12 and 13  of 3D math Primer for Graphics and Game Development by fletcher Dunn and IanParberry.I'm very sorry if this question annoys anyone, i just need to know if im correct.ive tried gamemath.com but no answers there, any other suggestions pllleasssse!   
  A lot of us won't have that book.How about you describe the exercises and then describe your solutions. Then someone should be able to help.   