I am new to number theory and i so far like it. I recently found this problem but there was no explaination of how they got it and i was wondering if any of you knew how they got it. It is this:(adsbygoogle = window.adsbygoogle || []).push({});

1/3+1/3^2+1/3^3... + 1/3^n=1/2(1-1/3^n)

Then they used:

1/4+1/4^2+1/4^3... + 1/4^n=1/3(1-1/4^n)

Now what i don't see is how they got that final equation (probably a dumb question) but i would appreciate it if anyone could help. Thanks.

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# Problem I Found

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