Matematica - Ecuatii si inecuatii. Functii

Ecuatii si inecuatii. Functii - Intrebarea 56

Mergi la:

Să se determine valorile reale pozitive ale lui $x$ pentru care are loc inegalitatea $open parentheses 3 to the power of x minus 9 close parentheses open parentheses l g x minus 1 close parentheses less or equal than 0$ .

x element of open square brackets 2 semicolon 10 close square brackets

x element of open square brackets 0 semicolon 10 close square brackets

x element of open square brackets 0 semicolon 2 close square brackets

Raspunsul este corect.

Raspunsul este gresit.

Explicatie:

Răspuns corect: A

Se realizează semnul funcției $f colon open parentheses 0 comma infinity close parentheses rightwards arrow straight real numbers comma space f left parenthesis x right parenthesis equals open parentheses 3 to the power of x minus 9 close parentheses open parentheses l g x minus 1 close parentheses$

$f left parenthesis x right parenthesis equals 0 left right double arrow x element of open curly brackets 2 comma 10 close curly brackets$

$f left parenthesis x right parenthesis less or equal than 0 comma space open parentheses for all close parentheses x element of open square brackets 2 semicolon 10 close square brackets f left parenthesis x right parenthesis greater or equal than 0 comma space open parentheses for all close parentheses x element of left parenthesis 0 semicolon 2 right square bracket union left square bracket 10 semicolon infinity right parenthesis$