Срочно! помогите решить буду рен благодарен!

1.
$3^{x+2}+ 3^{x-1} < 28$
$9*3^{x}+ \frac{1}{3}*3^{x} < 28$
$\frac{28}{3}*3^{x} < 28$
$3^{x} < 3$
x < 1

2.
17" alt="2^{x-1}+2^{x+3} > 17" align="absmiddle" class="latex-formula">
17" alt=" \frac{1}{2} *2^{x}+8*2^{x} > 17" align="absmiddle" class="latex-formula">
17" alt=" \frac{17}{2} *2^{x}> 17" align="absmiddle" class="latex-formula">
2" alt=" 2^{x}>2" align="absmiddle" class="latex-formula">
x > 1

3.
$2^{2x-1}+2^{2x-2}+2^{2x-3} \geq 448$
$4*2^{2x}+2*2^{2x}+2^{2x} \geq 448*8$
$7*2^{2x}\geq 448*8$
$2^{2x}\geq 64*8$
$2^{2x}\geq 2^{6+3}$
$2x \geq 9$
$x \geq \frac{9}{2}$

4.
$5^{3x+1}-5^{3x-3} \leq 624$
$5*5^{3x}- \frac{1}{125}*5^{3x} \leq 624$
$\frac{624}{125}*5^{3x} \leq 624$
$5^{3x} \leq 125$
$125^{x} \leq 125$
x ≤ 1