Write the resulting set using the listing method a 5 7 8 13

Write the resulting set using the listing method:

   a. {5, 7, 8, 13} { – 7, – 5, 8, – 13}       _____________________________

   b. {xIx^5=32}                   _____________________________

   c. {3, 21, 6, 12} { – 3, – 21, – 6, – 12}       _____________________________

Solution

a)

U means listing all the elements in both sets:

Thus, we have

{5, 7, 8, 13} { – 7, – 5, 8, – 13}

= {5, 7, 8, 13, – 7, – 5, – 13} [ANSWER]

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b)

As

x^5 = 32

then

x = 2

Thus, this set is {2}. [ANSWER]

(Do you include the complex roots? I only included the real roots here.)

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c)

means listing the elements common to both sets. Hence,

{3, 21, 6, 12} { – 3, – 21, – 6, – 12}

As there is no common element in both sets, then

{ } [ANSWER, empty set]