\frac{x}{y}=\frac{1+\sqrt5}{2}
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\frac{x}{y} = \frac{x+y}{x}
L=\frac{x}{y} lewa strona równania
x=1+\sqrt5 , y=2
P=\frac{x+y}{x}=\frac{1+\sqrt5+2}{1+\sqrt5}=\frac{3+\sqrt5}{1+\sqrt5}=\frac{(3+\sqrt5)(1-\sqrt5)}{(1+\sqrt5)(1-\sqrt5)}=\frac{3-3\sqrt5+\sqrt5-5}{1-5}=
\frac{-2-2\sqrt5}{4}=\frac{-\not2^1(1+\sqrt5)}{-\not4^2}=\frac{1+\sqrt5}{2}
L=P co należało wykazać