Topic 1 - 1.1 - Absolute Value, Subsets, & Elements of Sets.

Absolute Value

Absolute value is the distance from zero.  (Magnitude)

Such as:  -4 is 4 units from zero and 4 is 4 units from zero, so they both have a distance of 4 from zero.

  |-4|  =  4      |2.5|  =  2.5        |-7|  =  7

Subsets & Elements of sets

P  =  {3, 5, 7, 9, 11}       Q  =  {1, 3, 5, 6, 7, 9, 11, 12, 15}

P  с  Q   P is a subset of Q.  P is part of Q.  All the elements in P are also in Q.  (True)

Q  с   P  (The c should have a line thru it)  Q is not a subset of P.  Some element of Q are not in P.  (true)

3   ε   P   3 is an element of P.   3 is listed in P.    (True)

3   ε   Q  (The ε should have a line thru it)    3 is not an element of Q.   3 is not listed in Q   (false)

Remember when you have the subset symbol (с) it means the set on the left has all of its elements in the set on the right.

Also if you have the element symbol (ε) it means what is on the left is in the set on the right.

Go to Hints 1.1, on my website, and you will see the correct symbols.

|-5^2|  -  |3^3|  =  |-25|  -  |27|  =  25  -  27  =  -2