document.write( "Question 30099: an extra credit for my honors math class. i cant figure it out for the life of me...\r
\n" ); document.write( "\n" ); document.write( "derive the formula A=Pe^rt from the general formula for compounding interestL A=P(1+r/n)^n*t\r
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Algebra.Com's Answer #16844 by Fermat(136)\"\" \"About 
You can put this solution on YOUR website!
\"A+=+P%281%2Br%2Fn%29%5Ent\" - interest compounded periodically
\n" ); document.write( "\"A+=+Pe%5Ert\" ------- interest compounded continuously
\n" ); document.write( "When interest is compounded continously, this means letting the number of periods in a year increase without bound.
\n" ); document.write( "In other words, we find the limit, as n tends to infinity of \"A+=+P%281%2Br%2Fn%29%5Ent\"
\n" ); document.write( "\"Lim+%281%2Br%2Fn%29%5Ent\"
\n" ); document.write( "\"n+-%3E+infty\"
\n" ); document.write( "Binomial theorem
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\n" ); document.write( "Applying the Binomial theorem to \"%281%2Br%2Fn%29%5Ent\", we get
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\n" ); document.write( "as \"n-%3E+infty\", \"1%2Fn+-%3E+0\", giving
\n" ); document.write( "\"1+%2B+tr+%2B+t%5E2r%5E2%2F2+%2B+t%5E3r%5E3%2F3%21+%2B+t%5E4r%5E4%2F4%21+...\"
\n" ); document.write( "\"1+%2B+%28rt%29+%2B+%28rt%29%5E2%2F2+%2B+%28rt%29%5E3%2F3%21+%2B+%28rt%29%5E4%2F4%21+...\"
\n" ); document.write( "and the above is the Maclaurin series for \"e%5E%28rt%29\"
\n" ); document.write( "i.e. \"%281%2Br%2Fn%29%5Ent+-%3E+e%5E%28rt%29\" as \"n+-%3E+infty\"
\n" ); document.write( "We wanted to find the limit, as n tends to infinity of \"A+=+P%281%2Br%2Fn%29%5Ent\" and we have the limit, as n tends to infinity, of \"%281%2Br%2Fn%29%5Ent\" which is \"e%5E%28rt%29\". We substitute \"e%5E%28rt%29\" for \"A+=+P%281%2Br%2Fn%29%5Ent\".
\n" ); document.write( "So for continuous compounding we can write,
\n" ); document.write( "\"A+=+Pe%5E%28rt%29\"
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