Question 404132
given: u = sqrt(x^2+y^2) 
solve: [(du/dx)/(du/dy)]
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du/dx = (1/2)(2x)/sqrt(x^2+y^2) = x/sqrt(x^2+y^2)
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du/dy = (1/2)(2y)/sqrt(x^2+y^2) = y/sqrt(x^2+y^2)
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Ans: x/y
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Cheers,
Stan H.
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