Question

Logaritimos

Assinale a alternativa que corresponde log3 81+log√2 16.

 

  9

  10

  13

  15

  12

Answer 1

 log3 81+log√2 16.
4 + log2^1/2 (16) = 
4 + 2 . (log2(16)) = 
4 + 2 . (4) =
4 + 8 = 
12 

Answer 2

Olá.

$log_{3} 81 + log_{\sqrt{2}} 16 \\ 3^x=81 \\ 3^x= 3^4 \\ x=4 \\ \\ \ (\sqrt{2})^x= 16\\ (2^{\frac{1}{2}})^2 = 2^4 \\ 2^{\frac{x}{2}}= 2^4 \\ \frac{x}{2}= 4 \\ x= 4.2 \\ x=8 \\ \\ \\\boxed{ log_{3} 81 + log_{\sqrt{2}} 16 = 4+8=12}$