3 mũ x + 3 mũ x + 2 = 810

$3$$^x$ + $3$$^x+2$ = $810$ ? 

Đáp án : $x$ = $4$

Giải thik các bước giải :

$3$$^x$ + $3$$^x+2$ = $810$ 

$\Longrightarrow$ $3$$^x$ + $3$$^x$ . $9$ = $810$ 

$\Longrightarrow$ $3$$^x$ . $1$ + $3$$^x$ . $9$ = $810$ 

$\Longrightarrow$ $3$$^x$ . ( $1$ + $9$ ) = $810$ 

$\Longrightarrow$ $3$$^x$ . $10$ = $810$ 

$\Longrightarrow$ $3$$^x$ = $810$  : $10$

$\Longrightarrow$ $3$$^x$ = #81# 

$\Longrightarrow$ $3$$^x$ = $3$$^4$

$\Longrightarrow$ $x$ = $4$

Vậy $x$ = $4$ 

$#IdolTikTok$