SOLUTION: Given the equation X = 1/x^2 - 1/y, find y when X = 1 3/4, x=1/2

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Question 1041178: Given the equation X = 1/x^2 - 1/y,
find y when X = 1 3/4, x=1/2

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Given the equation X = 1/x^2 - 1/y,
find y when X = 1 3/4, x=1/2
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X = 1/x^2 - 1/y
Solve for y
x + 1/y = 1/x^2
1/y = 1/x^2 - x = 1/x^2 - x^3/x^2 = (1-x^3)/x^2
Invert
y = x^2/(1-x^3)
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@ x = 1 3/4 = 7/4, y = (49/16)/(1 - 343/64)
y = (49/16)/(-279/64) = -196/279
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Do the 2nd one the same way.