Question 992191
I need isolate "s" in this problem: 
P=f/2(1+sqrt(1+4s^2/f^2)) 
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2 = f[1+sqrt((f^2+4s^2)/f^2)]
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2 = f[1+(1/f)sqrt(f^2+4s^2)]
====
2 = [f+sqrt(f^2+4s^2)]
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2-f = sqrt(f^2+4s^2)
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4-4f+f^2 = f^2 + 4s^2
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4s^2 = 4-4f
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s^2 = 1 - f
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s = sqrt(1-f)
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Cheers,
Stan H.
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