In a certain sequence, the term \(t_n\) is defined as \(t_n=3t_{n-1}-2t_{n-2}\) for all \(n > 2.\) If \(t_1=-2\) and \(t_2=-1,\) then \(t_4=\)
A. -10
B. -8
C. -3
D. 1
E. 5
Answer: E
Source: Magoosh
In a certain sequence, the term \(t_n\) is defined as \(t_n=3t_{n-1}-2t_{n-2}\) for all \(n > 2.\) If \(t_1=-2\) and
This topic has expert replies
GMAT/MBA Expert
- Brent@GMATPrepNow
- GMAT Instructor
- Posts: 16207
- Joined: Mon Dec 08, 2008 6:26 pm
- Location: Vancouver, BC
- Thanked: 5254 times
- Followed by:1268 members
- GMAT Score:770
Given: term_(n) = 3term_(n-1) - 2term_(n-2)
So, for example, term_3 = 3term_(3-1) - 2term_(3-2) = 3term_2 - 2term_1 = 3(-1) - 2(-2) = 1
Similarly, term_4 = 3term_3 - 2term_2 = 3(1) - 2(-1) = 5
Answer: E