Geometric series introduction | Algebra 2 | Khan Academy

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A geometric series is the sum of the first few terms of a geometric sequence. For example, 1, 2, 4, 8,... is a geometric sequence, and 1+2+4+8+... is a geometric series. See an example where a geometric series helps us describe a savings account balance.

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[jonschwann]

This is wrong... that is 105% growth per year until 4 minutes. it should either be just 1000(1.05)^(n-1) or 1000 + 1000(.05) + 1000(.05)^2 ... etc. rather than 1000 + 1000(1.05 + etc...

[lofo_]

For everyone struggling on how he got the solution for the first one he keeps depositing 1000$ each year and since that happens when you deposit more money the $ from the previous year accumulates interest leading to number 3 being 1000 + 1000(1.05) + 1000(1.05)^2 since the 1000 is the amount being deposited in year 3 and the 1000(1.05) is the money being deposited in year 2 and the 1000(1.05)^2 is the money deposited in year 1.

[spurti]

excuse me khan academy how did you get 1.05 cuz it seems like vudoo magic??? and also why would you divide $1050/1000 to get 1.05

[hazelnoot]

1000(1.05)^number of years-1. Got it👍🏽

[yuvrajsahu]

Mujhe sir fire extinguisher k liye vidio chahiye