Question

Pls help i need a good grade in english !!

Answer 1

Recursive formula →
`a_n=-9n+19`

Explanation:

Recursive formula given for the sequence is,

`a_1=10` and
`a_n=a_(n-1)-9`

Therefore, sequence will be,

10, 1, -8, -17........

Explicit formula for an arithmetic sequence is,

`a_n=a_1+(n-1)d`

Here, n = number of term

d = common difference

Therefore, recursive formula will be,

`a_n=10+(n-1)(-9)`

= 10 - 9n + 9

= 19 - 9n

`a_n=-9n+19`