Let A 0 1 2 1 Determine whether 1 1 is in col 4SolutionNote

Let A = [0 1 -2 1] Determine whether [1 -1] is in col 4

Solution

Note that since first entry of first column is 0 so the first entry in the col A ie span of column vectors of A is determined only by the second column.

Let, first column be :c1 and second be c2

And let given vector be:ac1+bc2

So b=1 as explained before.

And ,-2a+1=-1

a=-1

So, given vector is in col A