Question

Решыте точно в прекрепе

Answer 1

$\displaystyle 4^x+4^1^-^x\geq 5\\4^x+4*4^-^x\geq 5\\\\4^x+4*\frac{1}{4^x}\geq 5\\ \\t+4*\frac{1}{t}\geq 5\\ \\t \in (0,1] \cup [4,+ \infty)\\4^x \in (0,1] \cup [4, + \infty)\\\\\left \{ {{4^x > 0} \atop {4^x\leq 1}} \right. \rightarrow 4^x\geq 4\\ \\\left \{ {{x \in R} \atop {x\leq 0}} \right. \rightarrow x\geq 1\\\\ x \in (- \infty,0], x\geq 1\\x \in (- \infty,0]\cup [1,+ \infty)$