3.5 Dimensions of the Four Subspaces

the zero column (except the combination with all coefficient s zero). And they also span the column space. Every other (free) column is a combination of the pivot columns. Actually the combinations we need are the three special solutions! Column 2 is 3 (column 1). The special solution is (−3,1,0,0,0). Column 3 is 5 (column 1). ................
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