SOLUTION: two positive numbers have a diference of d.Their reciprocals have a difference of r.Find an expression for their product,xy,in terms of d and r.

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Question 758047: two positive numbers have a diference of d.Their reciprocals have a difference of r.Find an expression for their product,xy,in terms of d and r.
Answer by stanbon(75887) About Me  (Show Source):
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two positive numbers have a diference of d.Their reciprocals have a difference of r.Find an expression for their product,ab,in terms of d and r.
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Equations:
a - b = d
1/a - 1/b = r
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Modify the 2nd equation to get ab:
(b-a)/ab = r
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So, ab = (b-a)/r
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But b-a = -d
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Therefore: ab = -d/r
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Cheers,
Stan H.
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