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Question
Find the fourth proportional to:
2xy, x2, y2
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Solution
Let A be the fourth proportional then
2xy : x2 = y2 : A
⇒ `(2xy)/x^2 = y^2/"A"`
⇒ A = `(x^2y^2)/(2xy)`
⇒ A = `(xy)/(2)`.
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