Matemática, perguntado por Jeremiasss, 1 ano atrás

Log√5 X =(9/4)

Calcule o valor de X
Atenção:√5 é a base

Soluções para a tarefa

Respondido por Niiya
1
Definição de logaritmo:

\boxed{\boxed{log_{b}(a)=c~~~\textless=\textgreater~~~b^{c}=a}}

Propriedades utilizadas:

\boxed{\boxed{\sqrt[n]{a^{m}}=a^{(m/n)}}}\\\\\\\boxed{\boxed{log_{b}(a)=\dfrac{log_{c}(a)}{log_{c}(b)}~~(mudanca~de~base~de~b~para~c)}}\\\\\\\boxed{\boxed{log_{(b^{n})}(a)=\dfrac{1}{n}\cdot log_{b}(a)~~~~(vem~da~propriedade~acima)}}
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log_{(\sqrt{5})}(x)=\dfrac{9}{4}\\\\\\log_{(\sqrt[2]{5^{1}})}(x)=\dfrac{9}{4}\\\\\\log_{[5^{(1/2)}]}(x)=\dfrac{9}{4}\\\\\\\dfrac{1}{(\frac{1}{2})}\cdot log_{5}(x)=\dfrac{9}{4}\\\\\\2\cdot log_{5}(x)=\dfrac{9}{4}\\\\\\log_{5}(x)=\dfrac{9}{4}\cdot\dfrac{1}{2}\\\\\\\boxed{\boxed{log_{5}(x)=\dfrac{9}{8}}}

Aplicando a definição de logaritmos:

log_{5}(x)=\dfrac{9}{8}~~~\textless=\textgreater~~~x=5^{(9/8)}

Então:

x=5^{(9/8)}\\\\x=5^{(8/8)+(1/8)}\\\\x=5^{(8/8)}\cdot5^{(1/8)}\\\\x=5^{1}\cdot\sqrt[8]{5^{1}}\\\\\boxed{\boxed{x=5\sqrt[8]{5}}}
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