MATH 121A Fall 2008 Instructor: Professor K. Sølna
Assignment #1 Due Tuesday Wed Oct 8th in class
(1) Page 13 # 2.
(2) Page 15 # 16
(3) Page 15 # 18
(4) Page 16 # 20
(5) Page 16 # 21
(6 ) Page 20 # 8(a,c)
(7) Let Abe an m-by-nmatrix of real numbers, and let Vbe the subset of IRnconsisting of all
vectors ~x∈IRmsuch that A·~x =~
0, where (as usual) ~
0 is the zero (column) vector in IRmand the
‘unknown’ vector ~x is a column vector in IRn; the ‘dot’ on the left side denotes ‘matrix multiplication.
Show that Vis a subspace of IRn.