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Revenue stamps of Rhodesia

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Revenue stamps of Rhodesia From Wikipedia, the free encyclopedia Jump to navigation Jump to search A Southern Rhodesia revenue stamp from 1937. Rhodesia , now divided between Zambia and Zimbabwe , first issued revenue stamps in 1890, and Zimbabwe continues to do so to this day. [1] Contents 1 British South Africa Company 2 Southern Rhodesia 3 Rhodesia 4 Zimbabwe 5 Northern Rhodesia 6 Zambia 7 See also 8 References 9 External links British South Africa Company [ edit ] The British South Africa Company issued revenue stamps for use in all of Rhodesia from 1890 to 1909. The first issue had four values from £1 to £10 and they bore the company's coat of arm. These were technically valid for postage but due to their high values they never actually saw postal use so they are regarded by many as purely revenue stamps. In 1896, some of these were surcharged with values betwe...

RFN museum

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Alternating polynomial of even degree is always greater than 0

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1 1 $begingroup$ Is it true that $$x^{2k} - x^{2k-1} + x^{2k-2} + .... + x^2 - x geq 0$$ for any $x$ real, and $kgeq 3$ a positive integer? It seems to be true for $kgeq 3$ , but it is not true for k=2. I thought about grouping the terms two by two but I didn't have much success. Edit: Nevermind it obviously fails for x in $(0,1)$ . Ignore the question. Edit 2: Actually, it seems that $$x^{2k} - x^{2k-1} + x^{2k-2} + .... + x^2 - x + 1 geq 0$$ for all positive integers $k$ . Any ideas on this one? algebra-precalculus inequality polynomials share | cite | improve this question edited Jan 6 at 22:51 T...