n^4 + 3n^2 + 2 is never a perfect square
14:00
sqrt2, sqrt5 and sqrt7 cannot be terms of the same geometric progression.
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Solve for all positive integers [Diophantine]
16:54
An integral with a classic result
6:08
Harvard University Admission Entrance Interview Tricks
21:38
(3 to the m) – (2 to the m) = 65 m=? MOST won’t FIGURE OUT how to solve!
25:46
integral of sqrt of tanx
17:08
Solving a Quartic Equation
12:25