Question

Calcule os seguintes logaritmos: a)log2 32.
b)log3 81.
c)log4 √2.
d)log10 0,001.
e)log7 343.

Answer 1

a) $log_{2} 32$ → $2^{x} = 32$  x = 5
b) $log_{3} 81$ → $3^{x} = 81$  x = 4

c) $log_{4}$ √2 → $4^{x}$ = √2

√2 = $2^{ \frac{1}{2} }$ 

4 = 2.2 = 2²

$(2^{2})^x = 2^ \frac{1}{2}$

x = 1/4

d) 

$log_{10}0,001$

$0,001 = 10^ -3$

$log_{10} 0,001 = log_{10} 10^-3 = -3.log_{10} 10 = -3$


e)

$log_{7} 343$

$7^{x} = 343$

7³ = 7.7.7 = 49.7 = 343

x = 3