\frac{R^{' 2} - r^{2}}{R_{v}^{2}} = \frac{1, 1^{2} - 0, 5^{2}}{1, 5^{2}} \approx 0, 43

${\frac{R'^2 - r^2}{R_v^2} = \frac{1,1^2 - 0,5^2}{1,5^2} \approx 0,43}$

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