This is just a pretty simple "riddle" that I have always liked a lot. I didn't come up with it, I actually got it off of a website a few years ago. I'm sure for some of you, it won't be new, but here goes..(adsbygoogle = window.adsbygoogle || []).push({});

x = x

x = 1 + 1 + ... + 1(x times)

x(x) = x(1 + 1 + ... + 1)

x^{2}= x + x + ... + x

D(x^{2}) = D(x + x + ... + x)

D(x^{2}) = D(x) + D(x) + ... + D(x)

2x = 1 + 1 + ... + 1(x times)

2x = x

2 = 1

Uh oh! What's going on with that real number line? :yuck:

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# Find the Error: Differentiation!

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