Question

pleaseeeeeeeeee helpppppppp
List the first four terms of a geometric sequence with t1 = 4 and tn = -3tn-1.
A. 12, 36, 108, 324
B. 12, 36, 48, 60
C. -12, 36, -108, 324
D. -12, 36, -48, 60
pleaseeeeeeeeeeeeee helpppppppppppppppppp

Answer 1

This doesn't make sense. Is t1 the first term? If so, -3(4)-1 would be 12, but there is no information on how to obtain the next term. Looking at the answers, you know it'll be 36, and since the sequence is geometric, it must multiply by the same number every time. 12 to 36 is multiplying by 3. 36 times 3 would be 108. Therefore you know the answer is going to have to be A or C. Does it tell you what the -3 and -1 stand for in the equation?

Answer 2

t1 = 4 and tn = -3tn-1.

Answer 3

nope doest seem like it

Answer 4

what wold make the difference if it was negative or not?

Answer 5

Well if it was multiplying by a -3, which it is and you have 12 as your first term. If you multiply that by -3, you get -36. Then multiply the -36 by -3 and you get 108. So the terms can go from negative to positive, but putting the 12 in the equation as t1, you get a positive because 2 negatives and one positive come out to be positive.