1003134709

Level: 
Project ID: 
1003134709
Accepted: 
1
Clonable: 
0
Easy: 
0
Find the sum of the second and the third term of the geometric sequence \( \{a_n\}_{n=1}^{\infty} \), if: \[ \begin{aligned} a_1-a_2&=b, \\ a_1+a_2&=-3b, b\in\mathbb{R}. \end{aligned}\]
\( -6b \)
\( -5b \)
\( -3b \)
\( -2b \)
\( 2b \)