Answer: Dim Col A = 4.
Step-by-step explanation:
Since we have given that
Matrix A has 5 rows and 8 columns.
And Nul A = 4
It implies that the rank of A would be
Number of columns - Nul A = 8 - 4 =4
So, rank A = 4
so, it has dim Col A = 4 also.
But the four vector basis lie in R⁵.
Hence, Dim Col A = 4.