> a = 2*i+1*j+1*k > > b= 2*i+-2*j+6*k > > c=0*i+0*j+9*k > > This is all that's given to me. When I enter this into MatLAB, it returns the error message, "??? Undefined function or variable 'k'." When I first looked at this problem, my first thought was, what are "i," "j," and "k." But I came to the conclusion that "i," and "j," are just the imaginary units, but I still have no idea what "k" is. Any help is appreciated!
That looks like a, b, c are meant to be quaternions. Note that as far as MATLAB is concerned, i==j unless you redefine one of them, and that is not what you want here.