Question

write in tabular form and set builder note .
1) A= { whole number less than 10 }
B= { multiples of 2 less than 20 }

Answer 1

Z = a set of whole numbers negative and positive.

A = { x  |  x ∈ Z,  x < 10 }
A = { .... -3, -2, -1, 0 , 1 , 2, 3, ... 8, 9 }
If negative numbers are not supposed to be there, then replace Z by N.


for B I assume only non-negative integers.  If you want -ve integers also, use Z in place of N.

B = { x  |  x ∈ N,  y ∈ N ,  x = 2y,  x < 20 }
B = { 0, 2, 4,6, ... 16, 18 }