Zadana je kružnica
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u koju su upisane tri sukladne kružnice tako da su sve četiri kružnice međusobno tangentne. U dio ravnine između tri manje kružnice upisana je nova kružnica
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koja izvana dodiruje svaku od tih triju kružnica. Taj postupak upisivanja kružnica se nastavlja u beskonačnost. Ako je radijus kružnice
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jednak
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, koliki je radijus kružnice
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? Rješenje upišite u znanstvenom zapisu s dvije decimale, sve bez razmaka (npr. 2.80*10^(-39)).
A circle
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is given, inside of which three congruent circles are inscribed, such that all four circles are mutually tangent. In the region of the plane between the three smaller circles, a new circle
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is inscribed, touching each of the three circles externally. This process of inscribing circles continues infinitely. If the radius of circle
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is
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, what is the radius of circle
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? Write your answer in scientific notation with two decimal places, with no spaces (e.g. 2.80*10^(-39)).
[lang=hr]
Zadana je kružnica $\omega_0$ u koju su upisane tri sukladne kružnice tako da su sve četiri kružnice međusobno tangentne. U dio ravnine između tri manje kružnice upisana je nova kružnica $\omega_1$ koja izvana dodiruje svaku od tih triju kružnica. Taj postupak upisivanja kružnica se nastavlja u beskonačnost. Ako je radijus kružnice $\omega_0$ jednak $28$, koliki je radijus kružnice $\omega_{39}$? Rješenje upišite u znanstvenom zapisu s dvije decimale, sve bez razmaka (npr. 2.80*10^(-39)).
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[lang=en]
A circle $\omega_0$ is given, inside of which three congruent circles are inscribed, such that all four circles are mutually tangent. In the region of the plane between the three smaller circles, a new circle $\omega_1$ is inscribed, touching each of the three circles externally. This process of inscribing circles continues infinitely. If the radius of circle $\omega_0$ is $28$, what is the radius of circle $\omega_{39}$? Write your answer in scientific notation with two decimal places, with no spaces (e.g. 2.80*10^(-39)).
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