Gustavo and yuki were asked to find an explicit formula for the sequence 19, 0, -19, -38...

Question

asked Apr 11, 2020 211k views

2 Answers

Mweber · Answer 1 · 2020-04-16T12:08:09+0000

Answer:

Explanation:

It's an arithmetic sequence.

$0-19=-19\\-19-0=-19\\-38-(-19)=-38+19=-19$

The difference is constant.

The explicit formula of an arithmetic sequence:

a_n=a_1+(n-1)d

Substitute:

$a_1=19,\ d=-19$

a_n=19+(n-1)(-19) use distributive property

$a_n=19-19n+19\\\\a_n=(19+19)-19n\\\\a_n=38-19n$