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8 votes
.Given logb^3 = 1/4 what is logb^9

2 Answers

10 votes

Answer:

1/2

Explanation:

Find the domain of the inequality:
\left \{ {{b > 0} \atop {b\\eq 1}} \right.

Solve the inequality: b > 0

Convert inequality to equation: b = 1

Solve the equation: b = 1

Convert equation to inequality: b ≠ 1

Find the intersection: 0 < b < 1 or b > 1

The domain of the inequality is:
\text{log}_b3=(1)/(4) ,0 < b, < b < 1 or
b > 1

Convert logarithm to exponential form:
b^{(1)/(4) } = 3, 0 <b<b1 or b > 1

Power on both sides: (b^1/4)^4=3^4, 0<b<1 or b > 1

Simplify using exponent rule (a^n)^m = a^nm:

b = 3^4, 0<b<1 or b > 1

Calculate the power:

b = 81 , 0<b<1 or b > 1

Find the intersection: b = 81

Substitute:
\text{log}_(81)9

Factorize the argument:
\text{log}_(81) 3^2

Express the logarithm of a power of an expression as the power times the logarithm of the expression:
2*\text{log}_(81) 3

Factorize the base:
2*\text{log}x_(3^4) 3

Rewrite the expression using the formula:
\text{log}_(a^n) b

to
((1)/(n) ) \text{log}_ab:
2*(1)/(4) *\text{log}_33

Apply the power law of logarithm to simplify the expression:


2*(1)/(4)

Reduce the expression to the lowest form:


(1)/(2)

Answer: 1/2

User LondonGuy
by
3.5k points
4 votes

Answer:


\log_b9=(1)/(2)

Explanation:


\textsf{Given}: \quad\log_b3=(1)/(4)


\textsf{To find }\log_b9, \textsf{ rewrite 9 as 3}^2:


\implies \log_b9=\log_b3^2


\textsf{Apply the Power log law}: \quad \log_ax^n=n\log_ax


\implies \log_b3^2= 2\log_b3


\begin{aligned}\textsf{If }\log_b3&amp; =(1)/(4)\\\\ \implies 2 \log_b3 &amp; =2 * (1)/(4)\\\\ &amp; = (2)/(4)\\\\ &amp; = (1)/(2)\end{aligned}


\textsf{Therefore}: \quad\log_b9=(1)/(2)

User Sharefa
by
3.4k points