Randi J.

asked • 02/02/16

explicit formula for geometric sequence 80, 40, 20, 10,...

So I'm supposed to write the explicit formula for the geometric sequence of 80, 40, 20, 10,... I got a sub n = 80(1/2) to the power of x? That's how my teacher wrote it, but i thought that you were supposed to do n-1 instead of x.. I'm also supposed to find the 7th term. When I did it my way i got a sub 7 = 1 1/4. But my teacher got 0.625. I'm just confused about why she did x instead of n-1.. Did I do it wrong or did she??

1 Expert Answer

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David W. answered • 02/02/16

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