Calculate high-order roots by hand

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Say you were asked to calculate a high-order root by hand. For example, the 13th root of 230,120,000 to 4 significant digits.

How would you do it? Would you do a manual Newton-Raphson iteration? Or perhaps a more crude sequence of repeated guessing? Would you manually calculate a Taylor series? What would be the fastest approach?

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One could use logarithms for such a problem .

For example ,lets take ,as you said, 230120000$^{1/13}$

Set Z = 230120000$^{1/13}$

log$_{10}$(Z) = $\frac{1}{13}$.log$_{10}$(230120000)

=$\frac{1}{13}$.(5+3.361954)

=$\frac{8.3619954}{13}$

log$_{10}$(Z)=0.64322723076

Z = 10$^{0.64322723076}$

Z = 4.397717

Therefore the 13$^{th}$ root of 230,120,000 is 4.397717

Virtually any root is calculable along with many other calculations if one has a log book handy.

$Note$ : I'm using base 10 but you can use any base with respect to the number whose root you want to find .