The Babylonian Square Root Algorithm
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If a number S is the square root of N, then SxS=N.
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So N/S=S.
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How this method works to find the square root of a number N:
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Make a guess, G.
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Check whether it is right by dividing N/G.
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If this equals G, you're done.
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If not, then G will be too small and N/G too big, or vice versa.
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The square root of N is in between these two.
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Average G and N/G to get your next guess.
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Repeat until G and N/G are close enough for the amount of accuracy you need.
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Try it! Change ONLY the numbers in shaded cells, C15 and A18:
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Find the square root of this number, N:
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GuessCheck: N/Guess
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32.333333333
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2.6666666672.625
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2.6458333332.645669291
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2.6457513122.64575131
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2.6457513112.645751311
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2.6457513112.645751311
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2.6457513112.645751311
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2.6457513112.645751311
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2.6457513112.645751311
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2.6457513112.645751311
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2.6457513112.645751311
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2.6457513112.645751311
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2.6457513112.645751311
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2.6457513112.645751311
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2.6457513112.645751311
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2.6457513112.645751311
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