I'm going to try a different, simpler, approach (tell me if you see anything wrong)Originally Posted bymacca101

we have the taylor series:

and we have the series...

now let's solve for:

but let's say

then rewrite the problem:

and then let's say

now remembering the taylor series:

we see that must be between -1 and 1, let's figure out what needs to be between:

and solve from there...

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