Question

решите неравенство (2,5)^2x+1>4/25

Answer 1

$2.5=\frac{25}{10}=\frac{25:5}{10:2}=\frac{5}{2}$
$\frac{4}{25}=\frac{2*2}{5*5}=(\frac{2}{5})^2=(\frac{5}{2})^{-2}$
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$(2.5)^{2x+1}>\frac{4}{25}$
$(\frac{5}{2})^{2x+1}>(\frac{5}{2})^{-2}$
$\frac{5}{2}>1$
$2x+1>-2$
$2x>-2-1$
$2x>-3$
$x>-3:2$
$>-1.5$
x є $(-1.5;+\infty)$