Question

Find two unit vectors orthogonal to a= <1, -4, 4> and b= <-5, 0, -4>

Enter your answer so that the first vector has a positive first coordinate

Answer 1

Do you know how to do a cross product?
c= a cross b is orthogonal to both a and b
-c= b cross a (negate the components of c ) to get a second vector
remember to divide c by its magnitude = sort(dot(c,c))

Answer 2

http://www.wolframalpha.com/input/?i=%281%2C-4%2C4%29+cross+%28-5%2C0%2C-4%29