Algebra .. equation

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Ok, this is waaaay off topic, but guess that's what these forums are for +_+

A kiss and a candy for anyone who can solve this equation (giving full detail on how he did that):

-4x^3+3x-1/2=0

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Use Newton's method (calculus)

Basically get an estimate/guess of X (say .2), then keep doing the iteration below (computer recommended for sanity).

Xn+1 = Xn- f(Xn)/f'(Xn)

f(x) = -4x^3+3x-1/2

f'(x) is the derivative of f(x)

Successive X's will be converge to the "real" root (they get more accurate each time), so keep doing it until it's accurate enough for you.

Here's a short cut:

http://www.math.sc.edu/cgi-bin/sumcgi/Newton.pl

Edit: Here's an explanation (semi-proof) why Newton's method works. Stop reading just after equation (5), we're not really interested in the rest (and it gets ugly too).

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If i posted some of my uni work could you write some technical reports for me please :D

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