n^4 + 3n^2 + 2 is never a perfect square
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Integrate 1(1+x^4) by factoring
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integral of sqrt of tanx
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a! b! = a! + b! + c!
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Find all positive integer n
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You probably haven't solved a quartic equation like this before!
14:57
Find the closest integer
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Harvard University Admission Entrance Interview Tricks
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