Question

find tn for the A.P.1,5,9,13,17.....

Answer 1

It will help you so much

Answer 2

Here,

$a = 1 \\ d = (9 - 5) = (5 - 1) = 4$

$tn = an$

$an = a + (n - 1)d \\ = > an = 1 + (n - 1)4 \\ = > an = 1 + 4n - 4 \\ = > an = 4n - 3.$

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