Taylor Polynomial

I suspect that your text book states an estimate for the error. Or you could have searched on line for it, getting a number of hits, like taylor polynomial error bound - Bing which says \(\displaystyle R_n\le \frac{f^{(n+1)}(z)|x- a|^{n+1}}{(n+ 1)!}\) where \(\displaystyle f^{(n+1)}(z)\) is the n+1 derivative at z, a is the point at which the the Taylor series is centered, x is value at which the value is calculated, and z is some value between a and x.
 
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