Write the first five terms of the sequence defined by the explicit formula

Question

asked Apr 24, 2019 179k views

2 Answers

Tomas Dolezal · Answer 1 · 2019-04-29T16:36:33+0000

Answer:

The correct answer option is: 19, 13, 3, -11, -29.

Explanation:

We are given the following explicit formula for an arithmetic sequence:

a_n=21-2n^2

So to find the first five terms of this sequence, we will substitute the values of
(num here in the given formula:

$a_1=21-2(1)^2\\\\a_1=19$

$a_2=21-2(2)^2\\\\a_2=13$

$a_3=21-2(3)^2\\\\a_3=3$

$a_4=21-2(4)^2\\\\a_4=-11$

$a_5=21-2(5)^2\\\\a_5=-29$

Therefore, the first five terms of the sequence defined by the explicit formula
a_n=21-2n^2 are 19, 13, 3, -11, -29.