some short and selected math problems of different levels in random order I try to keep the ans simple
Sunday, January 29, 2017
2017/003) Show that for a,b,c all different \sqrt[3]{a-b} + \sqrt[3]{b-c} + \sqrt[3]{c-a} != 0
if \sqrt[3]{a-b} + \sqrt[3]{b-c } + \sqrt[3]{c-a} = 0
then using (x + y + z = 0) =>x^3 + y^3 + z^3 = 3xyz
we get 0 = 3\sqrt[3]{(a-b)(b-c)(c-a)} giving a = b or b= c or c=a.
so if all are different result cannot be zero.
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