Question

1 O valor de x em log x 64 = 3 é:

a) 8
b) 2
c) 4
d) 6

2 Sabendo-se que log7 = 0,845 e log8 = 0,903, podemos calcular log56 como:
a) 0,058
b) 1,748
c) 1,69
d) 0,787

Answer 1

$\boxed{\begin{array}{l}\tt 1)\\\sf \ell og_x64=3\\\sf x^3=64\\\sf x=\sqrt[\sf3]{\sf 64}\\\sf x=4\\\huge\boxed{\boxed{\boxed{\boxed{\sf\maltese~alternativa~c}}}}\end{array}}$

$\boxed{\begin{array}{l}\tt 2)\\\sf\ell og7=0,845~~\ell og8=0,903\\\sf \ell og56=\ell og(7\cdot8)=\ell og7+\ell og8\\\sf\ell og56=0,845+0,903\\\sf \ell og56=1,748\\\huge\boxed{\boxed{\boxed{\boxed{\sf\maltese~alternativa~b}}}}\end{array}}$