Question

calcule log b 15, sendo log b 3= x e log b 5= y.​

Answer 1

• Propriedade usada

$\log_ba\cdot c=\log_ba+\log_bc$

Solução:

Temos que $15=3\cdot5$, então

$\log_b15\\\\\\=\log_b3\cdot5\\\\\\=\overbrace{\log_b3}^{x}+\overbrace{\log_b5}^y\\\\\\=x+y\\\\\Rightarrow \boxed{\boxed{\log_b15=x+y}}$