Use derivatives to estimate the value of (27.5)^(1/3). Compare the answer to the calculator answer---to how many decimals do the two answers agree?
f[x_]:=x^(1/3)
f1[x_]=D[f[x],x]
N[f[27]+f1[27]*(27.5-27),10]
N[f[27.5],10]
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