Write the following sets in the set-builder form:

{2, 4, 6, . . .}

Natural numbers are 1, 2, 3, 4, 5, 6……..

Even natural numbers are 2, 4, 6, 8……..

∴ the given set is set of all even natural numbers

The set in the set-builder form is

A= {x : x=2k for unique value of k, k <0}