Answer:
[tex]\log_721=x[/tex]
Step-by-step explanation:
We have been given the exponential function [tex]7^x=21[/tex]
We know the relation between exponential and logarithmic function
[tex]\text{if }y=b^x\Rightarrow\log_b(y)=x [/tex]
Comparing, this with the given equation, we get
y = 21
b = 7
x = x
Thus, using the relation, we have
[tex]7^x=21\\\\=\log_721=x[/tex]
Therefore, the equivalent logarithmic equation is
[tex]\log_721=x[/tex]
