Question

Will fan and Medal.
Find the 8th term of the geometric sequence.
1, -2, 4, -8,

Answer 1

what pattern do you notice here?

Answer 2

It's going back from positive to negative. But the middle numbers its jumping up and down each time.

Answer 3

you are multiplying times -2 each time, right?

Answer 4

so, starting from the 1st term, you need to multiply times -2 once to get to the second term.

Answer 5

And you'd keep going from there correct?

Answer 6

and starting from 1st term, you need to multiply times -2, 2 times , to find the 3rd term

Answer 7

and starting from the 1st term, you need to multiply times -2, 3 times, to find the 4th term

Answer 8

this way, you need to multiply times -2, 'n-1' number of times, to find the nth term.

Answer 9

and so, you need to multiply times -2, 7 times to find the 8th term

Answer 10

Oh, I see what you are doing there.

Answer 11

\(1\times (-2)^7=a_8\)

Answer 12

see why this is the 8th term?

Answer 13

(and all you need to do is to calculate that)
I got to go, apologize, and you welcome.

Answer 14

Yes, I understand now. I was confused but I think you gave me a very easy way how to solve it. Thank you!