Express One Logarithm in Terms of Another

The question gives a logarithmic relationship (e.g., log_a b = k) and asks the student to express a different logarithmic quantity in terms of the given variable(s) using change-of-base and algebraic manipulation.

gaokao 2020 Q8 5 marks View
If $a \log _ { 3 } 4 = 2$ , then $4 ^ { - a } =$
A. $\frac { 1 } { 16 }$
B. $\frac { 1 } { 9 }$
C. $\frac { 1 } { 8 }$
D. $\frac { 1 } { 6 }$
isi-entrance 2014 Q2 View
If $\log_{12} 18 = a$, then $\log_{24} 16$ equals
(A) $\dfrac{8 - 4a}{5 - a}$ (B) $\dfrac{4a - 8}{a - 5}$ (C) $\dfrac{4 + 8a}{5 + a}$ (D) None of these
turkey-yks 2010 Q26 View
$$\log_{3} 5 = a$$
Given this, what is the value of $\log_{5} 15$?
A) $\frac{a}{a+1}$
B) $\frac{a+1}{a}$
C) $\frac{a}{a+3}$
D) $\frac{a+3}{a}$
E) $\frac{4a}{3}$
turkey-yks 2013 Q6 View
For real numbers x and y
$$2 ^ { x } = 6 ^ { x + y - 1 }$$
Given this, what is $3 ^ { \mathbf { x } }$ in terms of y?
A) $3 ^ { 1 - y }$
B) $6 ^ { 1 - y }$
C) $6 ^ { y }$
D) $9 ^ { - y }$
E) $9 ^ { 1 + y }$