Find N to Solve Summation Math Problem - Get Help Now!

Thread starter tomboi03
Start date Dec 6, 2008
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Summation

Dec 6, 2008

tomboi03

Find an N so that

0< e-\sum 1/n! < 10^-14

n=0

I seriously don't know how to go about this problem.
Please help me out.

Thanks

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Dec 6, 2008

lurflurf

Homework Helper

since we know
e=1+1+1/2+1/6+...+1/n!+...
e-(1+1+1/2+1/6+...+1/n!)=1/(n+1)!+...<1/(n*n!)
so chose n at least so large that
1/(n*n!)<10^-14

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