Estimating golden ration by simulation

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I've been looking at Monte Carlo simulation recently, and have been using it to approximate constants such as π (circle inside a rectangle, proportionate area).

However, I'm unable to think of a corresponding method of approximating the value of Φ [Golden ratio ] using Monte Carlo integration or any other simulation.

Do you have any pointers on how this can be done?

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The golden triangle is an acute isosceles triangle with a vertex angle of $36^{\circ}$ and base angles of $72^{\circ}$. The ratio of the leg to the base is the golden ratio, $\Phi$, so the area of the triangle is $A=bh/2=\Phi\cos(\pi/10)/2$. This should work nicely in a Monte Carlo simulation.

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Another simple way that's along the lines of what you've done before, is just to monte-carlo evaluate the integral $$ \ln \phi = \int_0^\frac{1}{2} \frac{1}{\sqrt{x^2+1}} \ \text{d}x$$

For instance, sample uniformly at random from the rectangle $[0, \frac{1}{2}] \times [0, 1]$, compute the proportion of times $y_n^2 (x_n^2+1) \leq 1$ double it (to account for using a rectangle of area $\frac{1}{2}$) and exponentiate it in order to get an estimate for $\phi$