How to calculate large exponents by hand?
How to calculate large exponents by hand like they did in ancient times? Is it something to do with Prosthaphaeresis? for example calculate $2^{15}$.
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$\begingroup$Use logarithms perhaps?
$$\log_{10} 2^{15} = 15\log_{10} 2 \sim 15\cdot0.3 =4.5$$ So that: $$2^{15} \sim 10^{4.5} = 10^4\sqrt{10} \sim3\cdot 10^4$$ Which is just 7% percent away, and can be done in your head as long as you remember that $\log_{10} 2 \sim 0.3$, which most engineers probably do.
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