Question

Solve: $a_n=\frac{3n^2}{2}+\frac{5n}{2}$ find the ${25}^{th}$ term.

Answer 1

Given,

$a_n=\frac{3n^2}{2}+\frac{5n}{2}$

Given, $n=25$

$\therefore a_{25}=\frac{3(25{)}^2}{2}+\frac{5\left(25\right)}{2}$

$=\frac{1875}{2}+\frac{125}{2}$

$=\frac{2000}{2}$

$=1000$