To be noted: the last two exercises, 2.15 and 2.16 were left unfinished, and will be left for another time.
10 lines
328 B
Text
10 lines
328 B
Text
Let's limit our argument for positive numbers:
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a+-wa * b+-wb = [(a-wa)*(b-wb), (a+wa)*(b+wb)]
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[a*b - a*wb - b*wb + wa*wb, a*b + a*wb + b*wa + wa*wb]
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if we assume wa*wb is insignificantly small, we get:
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a*b+-(a*wb+b*wa)
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tolerances are the following:
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ta = wa/a
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tb = wb/b
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tab = (a*wb+b*wa)/(a*b) = (a*b*tb + a*b*ta)/(a*b) = ta+tb
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