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- [Narrator] In this self check exercise,

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we want you to use the
mathematical set operators

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to combine the two sets
that we're showing you

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as part of the problem statement here,

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and produce the results shown

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in parts A through D down below.

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So using the operators that
you just learned about,

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why don't you pause the
video and give that a shot,

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then come back here for the answers?

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Okay, let's talk about
the possibilities here.

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So, for part A here,

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the resulting set should contain only 30.

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And if you take a look here,

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you'll see that 10 and 20 are common

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between these two sets.

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Five is not in common,

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but since the result only has 30 in it,

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it appears what we're trying to do here

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is calculate the difference
between the sets.

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So when I subtract the right hand set

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from the left hand set,

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the set difference is going to consist of

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the elements in the left
that are not in the right,

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and the only such element
in this case is 30.

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So let me reveal my answer.

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Here is the minus operation
for set difference,

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and if I execute that,

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indeed I get 30.

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Now in this next one,

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we get five, 15, and 30,

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and if you look carefully
at all the values here,

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10 and 20 are common
between these two sets,

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but five and 15 on the right side

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and 30 on the left side

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are differences between the two sets.

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So this appears to be
a symmetric difference.

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And if we go ahead and take a look

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at this next solution here,

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we're using the symmetric
difference operator,

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and indeed we do get the
result specified in part B.

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Now if you look at part C here,

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the resulting set has everything

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that's unique to both of these sets,

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so this appears to be a union operation.

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So I'll go ahead and reveal

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the use of the union operator here,

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and indeed we get the
values shown in part C.

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And finally, we want to do
an intersection as well,

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and if you look at part D's answer,

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the intersection of these two sets

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are the values 10 and 20,

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which are in both the left
and the right operand.

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So just to demonstrate the intersection

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with the ampersand operator there,

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you can see that indeed we
get 10 and 20 as our result.