<h3>
Answer: -64</h3>
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Work Shown:
We have a geometric sequence
a = first term = -1
r = common ratio = (second term)/(first term) = 2/(-1) = -2
nth term
a(n) = a*(r)^(n-1)
a(n) = -1*(-2)^(n-1)
Now plug in n = 7 to get the 7th term
a(n) = -1*(-2)^(n-1)
a(7) = -1*(-2)^(7-1)
a(7) = -1*(-2)^6
a(7) = -1*(64)
a(7) = -64
The first seven terms are
-1, 2, -4, 8, -16, 32, -64
To get each new term, we multiply the last term by the common ratio -2