Question

Me ajuda na 8 e 9 PLS

Answer 1

$log_{10} 0,001=a \\ \\ log_{10} ( \frac{1}{1000})=a \\ \\ log_{10}( \frac{1}{ 10^{3} }) =a \\ \\ log_{10} 10^{-3} =a \\ \\ 10^{a}= 10^{-3} \\ \\ a=-3$

$log_{ \frac{1}{2} } ( \frac{1}{64} )=b \\ \\ log_{ \frac{1}{2} } ( \frac{1}{ 2^{6} } )=b \\ \\ log_{ \frac{1}{2} } 2^{-6} =b \\ \\ ( \frac{1}{2} )^b = 2^{-6} \\ \\ 2^{-b}= 2^{-6} \\ \\ -b=-6 \\ \\ b=6$

$3. log_{2}8=c \\ \\ 3. log_{2} 2^{3}=c \\ \\ 9. log_{2}2=c \\ \\ c=9$

ax² + bx + c = 0

- 3x² + 6x + 9 = 0

3x² - 6x - 9 = 0 (dividindo tudo por três).

x² - 2x - 3 = 0

Δ = (-2)² - 4 . 1 . (-3)

Δ = 4 + 12 = 16

x = (2 +/- √16)/2

x = (2 +/- 4)/2

x' = (2 + 4)/2 = 6/2 = 3

x" = (2 - 4)/2 = -2/2 = -1

S = {-1 ,3}.