Respuesta :

Your answer is D.a1=13;an=an−1+2

This question is based on the recursive rule.Therefore, the correct option is d, i.e. [tex]\bold{a_1 = 13, {a_n = a_n_-_1+ 2}}[/tex] .

Given:

[tex]a_n = 2n+11[/tex]

We need to determined the  recursive rule for [tex]a_n = 2n+11[/tex].

Now putting  n= 1 in given expression.

We get,

[tex]a_1= 2(1) + 11\\a_1 = 2 + 11\\a_1 = 13[/tex]     ........(1)                [tex]a_2= 2(2) + 11\\a_2 = 4 + 11\\a_2= 15[/tex]           .......(2)          

If we put n = 1 in  option (a),

We get,

[tex]a_2= a_2_-_ 1+11\\a_2= 13+11\\ a_2 = 24[/tex]

Hence, the value of  [tex]a_2[/tex] is not equal to the 15. Therefore. (a) option is wrong.

Now, check  option (d),

Putting n= 1, we get,

[tex]a_n = a_n_-_1+ 2\\a_2= a_2_-_1+2\\a_2=a_1+2\\a_2=13+2\\a_2=15[/tex]

Therefore, the correct option is d, i.e. [tex]\bold{a_1 = 13, {a_n = a_n_-_1+ 2}}[/tex].

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For more details, prefer this link:

https://brainly.com/question/23789371