Question

Знайдіть область визначення функції f(x)=(√log0,4(x)+1)​

Answer 1

$\displaystyle\bf\\f(x)=\sqrt{\log_{0,4}x+1 } \\\\\\\left \{ {{x > 0} \atop {\log_{0,4}x+1\geq 0 }} \right. \\\\\\\left \{ {{x > 0} \atop {\log_{0,4}x\geq -1 }} \right. \\\\\\\left \{ {{x > 0} \atop {x\leq 0,4^{-1} }} \right.\\\\\\\left \{ {{x > 0} \atop {x\leq 2,5 }} \right.\\\\\\Otvet \ : \ D(f)=\Big(0 \ ; \ 2,5\Big]$