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Sum Of A G.p. (1 Viewer)
- Thread starter jake2.0
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desmond.thai
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If r > 1, S<sub>n</sub> = a(r<sup>n</sup>-1)/(r-1)
If r < 1, S<sub>n</sub> = a(1-r<sup>n</sup>)/(1-r)
Hope that helps.
If r < 1, S<sub>n</sub> = a(1-r<sup>n</sup>)/(1-r)
Hope that helps.
Last edited:
Raginsheep
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Other way around?
Doesn't really matter though. The difference will come come out in the working.
Doesn't really matter though. The difference will come come out in the working.
H
housemouse
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Apparently the one with r > 1 is easier to use
desmond.thai
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whoops, thanks for seeing the mistake.
who_loves_maths
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Don't stress out about G.P.'s ppl,
after all, the greatest French mathematician (and generally the greatest intuitionist) of all time Henri Poincare did not even know how to prove the formula for the sum of a G.P. during a matriculation exam!
(of course, he was under pressure from being late to the exam and all, but still... )
so you may all discover the hidden mathematical genii within you yet!
P.S. True story.
after all, the greatest French mathematician (and generally the greatest intuitionist) of all time Henri Poincare did not even know how to prove the formula for the sum of a G.P. during a matriculation exam!
(of course, he was under pressure from being late to the exam and all, but still... )
so you may all discover the hidden mathematical genii within you yet!
P.S. True story.