Question

1. find the sum of a3,-a2+3a3+4a,-7-2a2-12a
2. Express the set in set builder form
a.{4,6,8,9,10,12,14,15,16,18,20}

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Answer 1

Answer:

1. 4a³-3a²-8a-7

2. A{x:x is a composite number where x belongs to N and x≤20}

Step-by-step explanation:

1. (a³)+(-a²+3a³+4a)+(-7-2a²-12a)

= a³-a²+3a³+4a-7-2a²-12a

= 4a³-3a²-8a-7

2. We can see that in the set A{4,6,8,9,10,12,14,15,16,18,20}, the elements are composite numbers, ≤ 20

So, we can write

A{x:x is a composite number where x belongs to N and x≤20}

hope it helps!