Question

If A=(1,2,3) and B=(4,5), find A x B and B x A. Determine n(A x B) and n(B x A). Could you please explain to me how to do these type of questions !

Answer 1

are these matrices???

Answer 2

these are sets

Answer 3

B x A=A x B = 1x4 +1x5 +2x4 + 2x5 + 3x4 + 3x5
n(A x B) = n x A x B

Answer 4

BxA is the set of ordered points like normal now; (b,a)

Answer 5

X x Y is what your used to seeing as a graph; with all the ordered pairs (x,y)

Answer 6

\[A\times B=\{(a,b)|a\in A, b\in B\}\]
\[A\times B=\{(1,4),(2,4),(3,4),(1,5),(2,5),(3,5)\}\]