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

[tomboi03]

Find an N so that

N​

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

 

[lurflurf]

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