Question

докажите неравенство:
с+5/с + с+5/5 < 4,
при с < 0

Answer 1

$frac{c+5}{c} + frac{c+5}{5} textless 4 \ frac{c+5}{c} + frac{c+5}{5} - 4 textless 0 \ frac{5(c+5)+c(c+5)-20c}{5c} textless 0 \ frac{5c+25+c^2+5c-20c}{5c} textless 0 \ frac{(5-c)^2}{5c} textless 0 \ left { {{(5-c)^2 textless 0} atop {5c textgreater 0}} right. to left { {{(5-c)^2 textgreater 0} atop {5c textless 0}} right. \ x to (-infty, 0)$

Answer 2

спасибо