That is my question.
How do we determine the basis for the image and the dimensions?
If you say the image of F is four-dimensional, then basis for the image of F can only be
span {(1/2,-1,0,0),(5/6,-2,1,-2/3),(17/12,-4,7/2,-7/3)} = span {(1/2,-1,0,0),(5/6,-2,1,-2/3)}
Is it correct now?Last time...