## Precalculus (6th Edition) Blitzer

$a_{1}=-1;a_2=5;a_3=-25;a_4=125;a_5=-625$
The general formula to find the nth term of a Geometric sequence is given as: $a_{n}=a_1r^{n-1}$ We make use of the recursive formula to get higher order terms from lower ones. So, the first $5$ terms of the sequence are $a_{1}=-1;a_2=5;a_3=-25;a_4=125;a_5=-625$