Find first term, common difference and $5^{th}$ term of the sequence which have the following $n^{th}$ term: $3n+7$.
Given: A sequence whose $n^{th}$ term: $3n+7$.
To do: To find first term, common difference and $5^{th}$ term of the sequence.
Solution:
$n^{th}$ term, $T_n=3n+7$
$T_2=3\times2+7=13$
$T_1=3\times1+7=10$
$T_5=3\times5+7=22$
Common difference $d=T_2−T_1$
$=13−10=3$
Hence, First term $a=10$, Common difference $d=3$ and Fifth term $T_5=22$
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