Question

Write the first five terms of the sequence defined by the explicit formula an=21-2n^2

Answer 1

The answer to the squence is either d or a i believe

Answer 2

Answer: D. 19, 13, 3, -11, -29

Step-by-step explanation:

The first five terms can be found by taking n= 1,2,3,4,5

The given sequence is :

$a_{n} =21-2n^{2}$

Substituting n = 1,2,3,4,5 we have :

$a_{1} =21-2(1^{2} )=21-2=19.$

$a_{2} =21-2(2^{2} )=21-8=13$

$a_{3} =21-2(3^{2} )=21-18=3$

$a_{4} =21-2(4^{2} )=21-32=-11$

$a_{5} =21-2(5^{2} )=21-50=-29$

The first five terms of the sequence are

D. 19, 13, 3, -11, -29