A set (-10.3; -7; 0; 2.6; 3) is given. Make a subset of it, consisting of non-negative numbers.

In order to compose a given subset, it is necessary to remember that a subset of a set A is a set B, each member of which belongs simultaneously to a set A and a set B. That is, each member (without exceptions) of set B is a member of set A.

Therefore, it remains for us to select from the available set of numbers only non-negative numbers (that is, numbers that are greater than or equal to zero) – this will be the desired set: 0; 2.6; 3.

Thus, if A = {-10.3; -7; 0; 2.6; 3}; B = {0; 2.6; 3}; moreover, for any element of the set В (в ϵ В) it is true that в ϵ А, then В is a subset of A.