Question

Find the $7^{th}$ term of the G.P. $2,-6,18,...$

• A. $1458$
• B. $2458$
• C. $3458$
• D. $4458$

Answer 1

The correct option is A $1458$

We know the formula,
$t_n=a{r}^{n-1}$
We need to find $7^{th}$ term i.e. $n=7$
Common ratio $=-3$
$a=2$
Thus $t_7=2\times (-3{)}^{7-1}$
$\Rightarrow t_7=2\times (-3{)}^6$
$\Rightarrow t_7=1458$