SOLUTION: If y^-4 = 1/25 and y<0, then y^3 - y = ?

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Question 1104594: If y^-4 = 1/25 and y<0, then y^3 - y = ?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
If y^-4 = 1/25 and y<0, then y^3 - y = ?
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(y^-4)^(-1/4) = (1/25)^(-1/4)
y = (1/5)^2 ^(-1/4) = (1/5)^-1/2 = (5)^(1/2) = sqrt(5)
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Ans: y^3 - y = 5^(3/2) - 5^(1/2)
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Cheers,
Stan H.
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