How do you solve \[8\ln (3x) = 48\]?
Answer
612k+ views
Hint: Here in this question, we have to solve the given equation to the x variable. The given equation is the logarithmic equation with one variable x, this can be solve by using some logarithmic property and add or subtract the necessary term from each side of the equation to isolate the term with the variable x, then multiply or divide each side of the equation by the appropriate value, while keeping the equation balanced then solve the resultant balance equation for the x value.
Complete step-by-step solution:
Consider the given equation
\[8\ln (3x) = 48\]--------(1)
Where x is the variable
Now, we have to solve the above logarithmic equation for the variable x
Divide 8 on both side of equation (1), then
\[ \Rightarrow \,\,\,\dfrac{8}{8}\ln (3x) = \dfrac{{48}}{8}\]
On simplification, we get
\[ \Rightarrow \,\,\,\ln (3x) = 6\]--------(2)
Take the inverse function (or place both sides as an exponent to e). This will cancel the using one of the logarithmic property i.e., \[{e^{\ln \left( x \right)}} = x\]
Equation (2) can be written as
\[ \Rightarrow \,\,\,{e^{\ln (3x)}} = {e^6}\]
By the logarithmic property
\[ \Rightarrow \,\,\,3x = {e^6}\]
We want to solve the equation for x, then we have divide both side of equation by 3, then
\[ \Rightarrow \,\,\,\dfrac{3}{3}x = \dfrac{{{e^6}}}{3}\]
On simplification, we get
\[ \Rightarrow \,\,\,x = \dfrac{{{e^6}}}{3}\]
As we know the approximate value of e is 2.718, on substituting the value, then
\[ \Rightarrow \,\,\,x = \dfrac{{{{\left( {2.718} \right)}^6}}}{3} \cong 134.39\]
Hence, the required solution is \[\,x = \dfrac{{{e^6}}}{3} \cong 134.39\].
Note: We solve the given equation for the variable x. As we know that the logarithmic function and exponential function are inverse of each other. So we take antilog on both sides and we simplify the given term. On simplification we use the simple arithmetic operations to the equation and hence we obtain the solution for the question.
Complete step-by-step solution:
Consider the given equation
\[8\ln (3x) = 48\]--------(1)
Where x is the variable
Now, we have to solve the above logarithmic equation for the variable x
Divide 8 on both side of equation (1), then
\[ \Rightarrow \,\,\,\dfrac{8}{8}\ln (3x) = \dfrac{{48}}{8}\]
On simplification, we get
\[ \Rightarrow \,\,\,\ln (3x) = 6\]--------(2)
Take the inverse function (or place both sides as an exponent to e). This will cancel the using one of the logarithmic property i.e., \[{e^{\ln \left( x \right)}} = x\]
Equation (2) can be written as
\[ \Rightarrow \,\,\,{e^{\ln (3x)}} = {e^6}\]
By the logarithmic property
\[ \Rightarrow \,\,\,3x = {e^6}\]
We want to solve the equation for x, then we have divide both side of equation by 3, then
\[ \Rightarrow \,\,\,\dfrac{3}{3}x = \dfrac{{{e^6}}}{3}\]
On simplification, we get
\[ \Rightarrow \,\,\,x = \dfrac{{{e^6}}}{3}\]
As we know the approximate value of e is 2.718, on substituting the value, then
\[ \Rightarrow \,\,\,x = \dfrac{{{{\left( {2.718} \right)}^6}}}{3} \cong 134.39\]
Hence, the required solution is \[\,x = \dfrac{{{e^6}}}{3} \cong 134.39\].
Note: We solve the given equation for the variable x. As we know that the logarithmic function and exponential function are inverse of each other. So we take antilog on both sides and we simplify the given term. On simplification we use the simple arithmetic operations to the equation and hence we obtain the solution for the question.
Recently Updated Pages
Master Class 12 Economics: Engaging Questions & Answers for Success

Master Class 12 Biology: Engaging Questions & Answers for Success

Master Class 12 Social Science: Engaging Questions & Answers for Success

Master Class 12 English: Engaging Questions & Answers for Success

Master Class 12 Maths: Engaging Questions & Answers for Success

Master Class 12 Physics: Engaging Questions & Answers for Success

Trending doubts
Fill the blanks with the suitable prepositions 1 The class 9 english CBSE

Difference Between Plant Cell and Animal Cell

What is the full form of pH?

On an outline map of India show its neighbouring c class 9 social science CBSE

What is pollution? How many types of pollution? Define it

What is momentum with examples class 9 physics CBSE

