Find:n^ th term of the A.P. 13, 8, 3, -2, .... - Vidyadip

Question

Find:$n^{th}$ term of the $A.P. 13, 8, 3, -2, ....$

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Answer

Given $A.P., 13, 8, 3, -2, .....$
Here,
First term,$ a = 13$
Difference,$ d = (8 - 13) = -5$
We have to find $n^{th}$ term,
So putting$ n = n$
We know, $n^{th}$ term of $A.P.$
$a_n = a + (n - 1)d$
$\Rightarrow a_n = 13 + (n - 1)(-5)$
$\Rightarrow a_n = 13 + (-5n + 5)$
$\Rightarrow a_n = 13 - 5n + 5$
$\Rightarrow a_n = 18 - 5n$
Hence,$ n^{th}$ term of given A.P. is $18 - 5n.$

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