Plz answer fast! Tell the correct answer(both parts), or else I will report you.
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Answer:
a1=7
an = an-1 * -2
Step-by-step explanation:
7,-14,28,-56
The first term is a1 so a1 = 7
We are multiply by -2 each time
7*-2 =-14
-14*-2 =28
28*-2 = -56
an = a(n-1) * -2