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$$x \arccos(x)+x/2=\cos(2x)$$

I dont know how to solve this one. It looks relatively easy but it is not, not for me at least.

Anybody to help?

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Hint, plot each side of the equation and see if there is a point of intersection. This will reveal a lot and hopefully provide you with a next step/approach to solving it. – Amzoti Oct 26 '12 at 22:48
I don't think there are ways of solving this other than graphically. – rubik May 17 '14 at 11:50

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