Question

найди множество натуральных решений неравенств 5/y<5/7

Answer 1

$frac{5}{y}<frac{5}{7}|:5\\frac{1}{y}<frac{1}{7}\\frac{1}{y}-frac{1}{7}<0\\frac{7-y}{7y}<0$

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_____________0_____________7_________

$xin (7;+infty)$