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# Inverse Trig Integral watch

1. (Original post by Barny)
So it's x^2/2 for x > 0 but -x^2/2 for x< 0?

Although, I'm still struggling to understand why exactly tan is a modulus here.

Is it also true that sqrt(sec^2(x)) = |secx| for example?
Yes, and

And Matt, very funny, but my point was that limits are needed for it to make sense
2. I always thought root(x^2) = +/- x which is slightly different to |x|, isn't it?
3. No, the square root symbol means the positive root, this is why there is a symbol in the quadratic formula
4. Well bugger me, fancy getting through 4 years of Maths without knowing that

So just to confirm, sqrt(x^2) = |x| is true for all x?
5. Yes. (All real x anyway) (Once we start dealing with complex numbers we sometimes give the symbol completely different meanings)

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Updated: August 31, 2008
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