Question

11. Se log 2 =0,30 e log 3 = 0,48 , o log 0,24 é:
a3,37
b) 2,47
c) 1,78
d) -1,62
e) -0,62

Answer 1

$\large\boxed{\begin{array}{l}\sf0,24=\dfrac{24\div4}{100\div4}=\dfrac{6}{25}\\\sf \ell og5=\ell og\bigg(\dfrac{10}{2}\bigg)=\ell og10-\ell og2\\\sf \ell og5=1-0,30=0,70 \\\sf \ell og6=\ell og(2\cdot3)=\ell og2+\ell og3\\\sf \ell og6=0,30+0,48=0,78\\\sf \ell og0,24=\ell og\bigg(\dfrac{6}{25}\bigg)=\ell og6-\ell og(25)\\\sf \ell og0,24=\ell og6-\ell og5^2\\\sf \ell og0,24=\ell og6-2\ell og5\\\sf \ell og0,24=0,78-2\cdot0,7\\\sf \ell og0,24=0,78-1,4\\\sf \ell og0,24=-0,62\end{array}}$

$\Large\boxed{\begin{array}{l}\huge\boxed{\boxed{\boxed{\boxed{\sf\maltese~alternativa~e}}}}\end{array}}$