Question

(1/3)^x+2+5*(1/3)^x+1-(1/3)^x< 7 ! !

Answer 1

$( \frac{1}{3} )^{x+2} +5* ( \frac{1}{3} )^{x+1} - ( \frac{1}{3} )^{x}\ \textless \ 7$
$( \frac{1}{3} )^{x}* ( \frac{1}{3} )^{2} +5* ( \frac{1}{3} )^{x}* ( \frac{1}{3} )^{1}- ( \frac{1}{3} )^{x} \ \textless \ 7$
$( \frac{1}{3} )^{x}*( \frac{1}{9}+ \frac{5}{3} -1)\ \textless \ 7$
$( \frac{1}{3} )^{x}* \frac{7}{9}\ \textless \ 7$
$( \frac{1}{3} )^{x}\ \textless \ 7: \frac{7}{9}$
$( \frac{1}{3} )^{x}\ \textless \ 9$
$( \frac{1}{3} )^{x}\ \textless \ ( \frac{1}{3} )^{-2}$
0<1/3<1, знак неравенства меняем:
x>-2