Question

log inbaza 2din x la a 2 plus 4 egal cu log in baza 2 din 8

Answer 1

"Log inbaza 2din x la a 2 plus 4 egal cu log in baza 2 din 8"


[tex]\it \log_2 x^2 +4 =\log_2 8 \Leftrightarrow 2\log_2x +4 =3 \Leftrightarrow 2\log_2x = 3 -4 \Leftrightarrow \\\;\\ \Leftrightarrow \it2\log_2x = -1 \Leftrightarrow \log_2 x =-\dfrac{1}{2}\Leftrightarrow x =2^{-\dfrac{1}{2}} \Leftrightarrow x=\dfrac{1}{\sqrt 2} \\\;\\ \Leftrightarrow x =\dfrac {\sqrt\it 2}{\it2}[/tex]