Sequences and Series (again) (1 Viewer)

Average Boreduser · Nov 30, 2022

How would someone approach these questions?

Drongoski · Nov 30, 2022

Q1.

$S_n = \frac {n}{2}(2a + (n-1)d) \\ \\ \text{ is simply the formula for sum of the 1st n terms of the the A.P.: a, a+d, a+2d, a+3d, . . . . }\\ \\ \text {whose n-th term is simply: } a_n = a+(n-1)d$

Q2.

$\text {The formula:} S_n = \frac {a(r^n -1)}{r-1} \text { is simply the formula for the sum of the 1st n terms of the G.P: }a, ar, ar^2, ar^3, ar^4 . . .. \\ \\ \text { with general term: } a_n = ar^{n-1}$

Average Boreduser · Nov 30, 2022

Wow, thanks man.

Sequences and Series (again) (1 Viewer)

Average Boreduser

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Drongoski

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Average Boreduser

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