If a+1/a =5 find the difference between a and 1/a
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If a+1/a = 5, then
a^2 + 1 = 5a, or a^2 - 5a + 1 = 0
a = 5+/-sqrt(5^2-4*1*1)/2*1
a = 5+/-sqrt(25-4)/2 = (5+/- sqrt21)/2 = (5+4.58)/2 and (5-4.58)/2
9.58/2 = 4.79 or 0.42/2 = 0.21
Therefore if a = 4.79, then 1/a = 0.21. Thus, the difference between the two is
4.79 - 0.21 = 4.68.
a^2 + 1 = 5a, or a^2 - 5a + 1 = 0
a = 5+/-sqrt(5^2-4*1*1)/2*1
a = 5+/-sqrt(25-4)/2 = (5+/- sqrt21)/2 = (5+4.58)/2 and (5-4.58)/2
9.58/2 = 4.79 or 0.42/2 = 0.21
Therefore if a = 4.79, then 1/a = 0.21. Thus, the difference between the two is
4.79 - 0.21 = 4.68.
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