Hi Masters,

I calculated 0.2 = e^(-x(ln2/700)) to find x.

But, I could not use a calculator also did not have any approximation for the value of ln.

So, I got x = 700(ln5 / ln2).

But the wolfram says the answer is x = 700((ln5+ 2i pi n) / ln2).

Can I ask where 2i pi n came from?

So, my answer which is just 700(ln5 / ln2) is wrong?

Thanks a lot.