Question

Rezolvati in R ecuatia : 4^x-10*2^x+16=0

Answer 1

$4^{x}-10* 2^{x}+16=0=> (2^{x})^{2} -10* 2^{x}+16=0$
$2^{x}=a=> a^{2} -10a+16=0; a_{1,2} =(2;8)=>$
$2^{x}=2, x=1; 2^{x}=8, x=3$
Solutia: x∈(1;3)