Question

1≤16^x≤2. ............

Answer 1

$1\leq16^{x}\leq2$

$2^{0}\leq2^{4x}\leq2^{1}$ т.к.2 >1 => знак не меняется

$0\leq4x\leq1$

$0\leq x \leq \frac{1}{4}$

x∈$[0:\frac{1}{4} ]$

Answer 2

1≤16^x≤2
{16^x≥1 ;16^x≥16^0;x≥0
{16^x≤2 ;2^(4x)≤2;4x≤1;x≤1/4

{x≥0
{x≤1/4

x€[0;1/4]