Answer:
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Step-by-step explanation:
Recursive Sequence
We are given the following sequence:
-1, 1, 5, 13...
It's required to find the recursive term for the sequence.
A recursive formula calculates each term as a function of one or more previous terms.
To find the recursive formula, we must find a pattern and transform it into a math expression.
Let's write the sequence, and below it, the difference of consecutive terms:
-1, 1, 5, 13...
+2, +4, +8
Note the difference between consecutive terms is always a power of 2, starting from 2^1, 2^2, 2^3.
The exponent is one less than the number of the term, thus:
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Thus:
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Testing:
n=1
(given).
n=2
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n=3

n=4

Answer is x= -14 because you divide each term by -3 and then simplify
For 2/5 cup, vanilla needed = 8 teaspoons
so, for 1 cup, it would be: 8 / 2/5
⇒8 × 5/2
⇒40/2
⇒20
In short, Your Answer would be 20 teaspoons
Hope this helps!