Question

Надо срочно плиз!!!!!!!!!!!!!!!!

Answer 1

1)
$log_2(4-x) \geq -3$
ОДЗ:
$4-x\ \textgreater \ 0$
$x\ \textless \ 4$

$log_2(4-x) \geq log_22^{-3}$
$log_2(4-x) \geq log_2 \frac{1}{8}$
$4-x \geq \frac{1}{8}$
$-x \geq \frac{1}{8} -4$
$-x \geq-3.875$
$x \leq 3.875$

-------------------------[3.875]-----------
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Ответ:  $(-$ ∞ $;3.875]$

2)
$27^{ \frac{1}{3} }+81^{ \frac{3}{4} }+log_{16} \frac{1}{8} =(3^3)^{ \frac{1}{3} }+(3^4)^{ \frac{3}{4} }+log_{2^4}2^{-3} =3+3^3-3* \frac{1}{4}log_22=$$=3+27-0.75=29.25$