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Is 1-1+1-1+1-1+...=12 really true

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How to solve a functional equation on the AIME

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My All-In-One Calculus Problem! (now in a matrix!)

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Proving the quadratic formula using calculus (just my attempt)

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Can we have a right triangle with sides 1, x and x^2 (but the hypotenuse is x)

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Integration by Accident

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So you want another logarithm triangle (w law of cosines this time!)

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Finding the volume of a 4d sphere

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My first triple improper integral via spherical coordinates

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This calculus proof is only for math majors (National Taiwan University entrance exam)

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Can factorial ever be 0

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Volume of revolution (single integral vs triple integral)

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A lovely calculus proof problem! (National Taiwan University entrance exam)

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How math majors use the intermediate value theorem!

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Brilliant minimum problem

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So you want the Gaussian integral trick again

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Why do mathematicians think disc=square

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How to welcome a math Phd friend at the airport

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How to rigorously prove that a limit is WRONG!

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Can f'(x)=f^-1(x)

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Simple limit but most students cannot prove it!

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How to find a delta for a specific epsilon (epsilon-delta definition of a limit)

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How to find a formula for delta (epsilon-delta definition of a limit)

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Brilliant Trig Identity Challenge!

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It’s not joke, it’s rigorous enough for physics… 😂

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My first abstract algebra problem in 14 years!

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Why are integrals so hard

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I’m sorry, I have been saying “let x=1” wrong for 13 years

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Can x^y=yx

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How many square roots does the 2x2 zero matrix have

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