SOLUTION: What is the 8th term of -3, -9, -27, -81

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Question 1151040: What is the 8th term of -3, -9, -27, -81
Found 2 solutions by MathLover1, MathTherapy:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

What is the 8th term of
-3, -9, -27, -81.........find pattern
-3
-9=-3%2A3%5E1+
-27=-3%2A3%2A3=-3%2A3%5E2+
-81=-9%2A9=-3%2A3%2A3%2A3=-3%2A3%5E3
generally: -3%2A3%5E%28n-1%29
8th term means n=8, and it is -3%2A3%5E%288-1%29=+-3%2A3%5E7=highlight%28-6561%29
some more terms:
-3, -9, -27, -81, -243,+-729, -2187, highlight%28-6561%29, -19683, -59049, -177147, ......


Answer by MathTherapy(10556) About Me  (Show Source):
You can put this solution on YOUR website!
What is the 8th term of -3, -9, -27, -81
Use the formula for a specific term of a G.P. (geometric progression/sequence): highlight_green%28matrix%281%2C3%2C+a%5Bn%5D%2C+%22=%22%2C+a%5B1%5Dr%5E%28n+-+1%29%29%29, where: 

Substitute all values for all variables, and you should be able to determine a%5B8%5D, or the 8th term of the sequence.