For the sets a = {a,b} and b = {a,b,c}, determine ax b, bx a, a2 = ax a and b2 = bxb.

Hello!

the cross product between sets is defined as:

if A = {a,b,c} and B = {1,2,3)

then

where the A took the place of the columns, and B for the files.

then if our sets are A = {a,b} and B = {a,b,c)

a) AxB

b) BxA

c) AxA

d) BxB

Hope it helps, i know that is kinda hard work with this kind of operations, i tried to make a kinda of map in the first part so you can replace the values of A and B and do the multiplications by yourself, if you have troubles don't doubt of asking.

D.  (-infinity, 2)

This is the interval

On this interval, the function curve is going downhill as you read it from left to right.

More technically, the function is decreasing on this interval because f(a) > f(b) where a < b. For example, f(0) > f(2) and note that 0 < 2.