0.2^(1-sqrt(2.5))/sqrt3(125^2-0.3^3)-cos(pi/sqrt(5))

$${\frac{{{\mathtt{0.2}}}^{\left({\mathtt{1}}{\mathtt{\,-\,}}{\sqrt{{\mathtt{2.5}}}}\right)}}{{\sqrt[{{\mathtt{3}}}]{{{\mathtt{125}}}^{{\mathtt{2}}}{\mathtt{\,-\,}}{{\mathtt{0.3}}}^{{\mathtt{3}}}}}}}{\mathtt{\,-\,}}\underset{\,\,\,\,^{\textcolor[rgb]{0.66,0.66,0.66}{360^\circ}}}{{cos}}{\left({\frac{{\mathtt{\pi}}}{{\sqrt{{\mathtt{5}}}}}}\right)} = -{\mathtt{0.897\: \!779\: \!501\: \!829\: \!020\: \!9}}$$

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