The late Tokugawa shogunate or last shogun (幕末; Bakumatsu) is the period between 1853 and 1867 during which Japan ended its isolationist foreign policy and modernized from a feudal shogunate to the Meiji government. It is at end of Edo period and preceeded by Meiji era.
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If the discriminant is positive, then there are two different solutions x, both of which ...