Answer:
- using the rule given: 2.5
- using an exponential rule: 7
Explanation:
Evaluating the linear rule given, for n = 1, we have ...
a1 = 7(1/2)(1) -1 = 7/2 -1 = 5/2 = 2.5
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We suspect you may intend the exponential function ...
an = 7(1/2)^(n-1)
Then, for n = 1, we have ...
a1 = 7(1/2)^(1 -1) = 7(1) = 7 . . . . the first term is 7
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When writing an exponential expression in plain text, it requires the exponential operator, a caret (^). If the exponent contains any arithmetic, as this one does, it must be enclosed in parentheses.