Question

Calcule o valor de x:
a) log x 8 = 3
b) log x $\frac{1}{16}$ = 2
c) log² x = 5

Answer 1

Resposta:

a) x = 2  

b) x = 1/4  

c) x = 32

a) logₓ 8 = 3    

x³ = 8  

x³ = 2³    

x = 2

b) logₓ 1/16 = 2  

x² = 1/16  

x² = 1  

     16  

x= √1  

   √16  

x = 1/4

c) log₂ x = 5  

2⁵ = x  

x = 2⁵  

x = 32

Answer 2

Explicação passo-a-passo:

$a)\\ \log_x8=3\\ \\ x^3=8\\ \\ x=\sqrt[3]{8} \\ \\ x=\sqrt[3]{2^3}=2^{3\over3}=2^1 \\ \\ x=2$

----------------------------------------------

$b)\\ \log_x{1\over16}=2\\ \\ x^2={1\over16}\\ \\ x=\sqrt{{1\over16}} \\ \\ x={1\over4}$

--------------------------------------------

$c)\\ \log_2x=5\\ \\ x=2^5\\ \\ x=32$