How do you solve \[3\log x = 1.5\]?
Answer
625.5k+ views
Hint: Here the question given is \[3\log x = 1.5\] and we need to solve for it.
First we will simplify it using the properties of logarithm and we will find two different expressions using the properties of logarithm and then use it to one another or substitute it in order to find the value of $x$.
Complete step by step answer:
In this question we are asked to solve the given expression \[3\log x = 1.5\]
Here we can transfer the given number $3$ to the power of $x$ and hold it
Transferring the real number as a power of the variable,
\[ \Rightarrow 3\log (x) = 1.5\]
On rewriting the term and we get,
$ \Rightarrow 3\log (x) = \log ({x^3})$
Then, we get
$ \Rightarrow \log ({x^3}) = 1.5$
Now back to the given expression. We know that any logarithm as a power of number is itself.
That is, ${10^{log(x)}} = x$
With this property, we can interpret or change the expression or also write it as,
$ \Rightarrow {10^{log({x^3})}} = {x^3}$
Now, we got $\log ({x^3}) = 1.5$ and ${10^{log({x^3})}} = {x^3}$
Therefore we can substitute the former in the place later. That is we will put $\log ({x^3}) = 1.5$in the second one.
Hence it becomes,
$ \Rightarrow {x^3} = {10^{1.5}}$
We can expand the RHS by
$ \Rightarrow {10^{0.5}} \times {10^{0.5}} \times {10^{0.5}}$
Also we can expand $x$ too, so we get
$ \Rightarrow x \times x \times x = {10^{0.5}} \times {10^{0.5}} \times {10^{0.5}}$
It ultimately means that,
$ \Rightarrow x = {10^{0.5}}$
Which also can be written as ${10^{\dfrac{1}{2}}}$,
$ \Rightarrow {10^{\dfrac{1}{2}}}$
On rewriting the term and we get
$ \Rightarrow \sqrt {10} $
Therefore the value of $x$ in \[3\log x = 1.5\] is $\sqrt {10} $.
Note: Logarithm is the exponent or power to which a base must be raised to yield a given number. That is, we can say that \[x\] is the logarithm of \[n\] to the base \[b\] if ${b^x} = n$, we can write it as \[x\; = {\text{ }}{\log _b}\;n\] .
For example, ${3^2} = 9$ therefore, $2$ is the logarithm of $9$ to base $3$ , or\[{\text{2 }} = {\text{ }}{\log _3}\;9\]. Like this, since \[{10^2}\; = {\text{ }}100\], then \[2{\text{ }} = {\text{ }}lo{g_{10}}\;100\] .
First we will simplify it using the properties of logarithm and we will find two different expressions using the properties of logarithm and then use it to one another or substitute it in order to find the value of $x$.
Complete step by step answer:
In this question we are asked to solve the given expression \[3\log x = 1.5\]
Here we can transfer the given number $3$ to the power of $x$ and hold it
Transferring the real number as a power of the variable,
\[ \Rightarrow 3\log (x) = 1.5\]
On rewriting the term and we get,
$ \Rightarrow 3\log (x) = \log ({x^3})$
Then, we get
$ \Rightarrow \log ({x^3}) = 1.5$
Now back to the given expression. We know that any logarithm as a power of number is itself.
That is, ${10^{log(x)}} = x$
With this property, we can interpret or change the expression or also write it as,
$ \Rightarrow {10^{log({x^3})}} = {x^3}$
Now, we got $\log ({x^3}) = 1.5$ and ${10^{log({x^3})}} = {x^3}$
Therefore we can substitute the former in the place later. That is we will put $\log ({x^3}) = 1.5$in the second one.
Hence it becomes,
$ \Rightarrow {x^3} = {10^{1.5}}$
We can expand the RHS by
$ \Rightarrow {10^{0.5}} \times {10^{0.5}} \times {10^{0.5}}$
Also we can expand $x$ too, so we get
$ \Rightarrow x \times x \times x = {10^{0.5}} \times {10^{0.5}} \times {10^{0.5}}$
It ultimately means that,
$ \Rightarrow x = {10^{0.5}}$
Which also can be written as ${10^{\dfrac{1}{2}}}$,
$ \Rightarrow {10^{\dfrac{1}{2}}}$
On rewriting the term and we get
$ \Rightarrow \sqrt {10} $
Therefore the value of $x$ in \[3\log x = 1.5\] is $\sqrt {10} $.
Note: Logarithm is the exponent or power to which a base must be raised to yield a given number. That is, we can say that \[x\] is the logarithm of \[n\] to the base \[b\] if ${b^x} = n$, we can write it as \[x\; = {\text{ }}{\log _b}\;n\] .
For example, ${3^2} = 9$ therefore, $2$ is the logarithm of $9$ to base $3$ , or\[{\text{2 }} = {\text{ }}{\log _3}\;9\]. Like this, since \[{10^2}\; = {\text{ }}100\], then \[2{\text{ }} = {\text{ }}lo{g_{10}}\;100\] .
Recently Updated Pages
Explain the Treaty of Vienna of 1815 class 10 social science CBSE

A Paragraph on Pollution in about 100-150 Words

What is BLO What is the full form of BLO class 8 social science CBSE

10 examples of friction in our daily life

Draw a diagram of nephron and explain its structur class 11 biology CBSE

Write structures of the following compounds i 2 Chloro3methylpentane class 11 chemistry CBSE

Trending doubts
1 GB equals how many MB?

Which is the hottest planet in the Solar system A Earth class 10 social science CBSE

Name any four life processes in living things class 10 biology CBSE

Identify the feminine form of noun nephew a shenephew class 10 english CBSE

Choose the feminine form of the given noun Fox AFoxess class 10 english CBSE

Write a factual description in about 100 words on class 10 english CBSE

