Question
Write the common difference of an A.P. whose $n^{th}$ term is $a_n = 3n + 7.$
✓
Answer
Given,
$a_n = 3n + 7$
Puting $n = 1, 2, 3, .....$
$a_1 = 3(1) + 7 = 3 + 7 = 10,$
$a_2 = 3(2) + 7 = 6 + 7 = 13,$
and $a_3 = 3(3) + 7 = 9 + 7 = 16$
Now, Common difference
$d = a_2 - a_1 = 13 - 10 = 3$
$d = a_3 - a_2 = 16 - 13 = 3$
Hence, common difference is $3$.
$a_n = 3n + 7$
Puting $n = 1, 2, 3, .....$
$a_1 = 3(1) + 7 = 3 + 7 = 10,$
$a_2 = 3(2) + 7 = 6 + 7 = 13,$
and $a_3 = 3(3) + 7 = 9 + 7 = 16$
Now, Common difference
$d = a_2 - a_1 = 13 - 10 = 3$
$d = a_3 - a_2 = 16 - 13 = 3$
Hence, common difference is $3$.
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