Subset in Math

Definition of Subdivisions

To understand the meaning of subsets, consider the illustration below:

A = {rickshaw, wagon, car, bus, train, ship, flying plane}
B = {cars, buses, fire trains, airplanes, ships}
C = {rickshaw, wagon, ship, train, bus}

If you notice, each member of set B is also a member of set A. We say that B is a subset of A, and is denoted by B⊂A. Similarly, each member of set C is also a member of set A so that C is a subset of A, and denoted by C⊂A.

What if with sets B and C?

If we consider the sets B and C, not all members of set B include set C, that is car and airplane. In this case, B is not the subset C, denoted B⊄ C. Conversely, not all members of set C include set B, namely pedicab and wagon. In this case, C is not a subset of B, denoted C⊄B.

Set P is said to be a subset of Q if each member of set P is also a member of the set Q, denoted by P⊄Q.
Set P is said to be not a subset of Q if there is a member of set P that is not a member of set Q, denoted P⊂Q.

So many articles this time. Sorry if there is a mistake.
Final words wassalamualaikum wr wb.

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