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HELLOOOO HELP PLEASE

HELLOOOO HELP PLEASE-example-1
User Koichirose
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1 Answer

4 votes

Answer:


2*log(x)+log(y)

Explanation:

So, there are two logarithmic identities you're going to need to know.

Logarithm of a power:


log_ba^c=c*log_ba

So to provide a quick proof and intuition as to why this works, let's consider the following logarithm:
log_ba=x\implies b^x=a

Now if we raise both sides to the power of c, we get the following equation:
(b^x)^c=a^c

Using the exponential identity:
(x^a)^c=x^(a*c)

We get the equation:
b^(xc)=a^c

If we convert this back into logarithmic form we get:
log_ba^c=x*c

Since x was the basic logarithm we started with, we substitute it back in, to get the equation:
log_ba^c=c*log_ba

Now the second logarithmic property you need to know is

The Logarithm of a Product:


log_b{ac}=log_ba+log_bc

Now for a quick proof, let's just say:
x=log_ba\text{ and }y=log_bc

Now rewriting them both in exponential form, we get the equations:


b^x=a\\b^y=c

We can multiply a * c, and since b^x = a, and b^y = c, we can substitute that in for a * c, to get the following equation:


b^x*b^y=a*c

Using the exponential identity:
x^(a)*x^b=x^(a+b), we can rewrite the equation as:


b^(x+y)=ac

taking the logarithm of both sides, we get:


log_bac=x+y

Since x and y are just the logarithms we started with, we can substitute them back in to get:
log_bac=log_ba+log_bc

Now let's use these identities to rewrite the equation you gave


log(x^2y)

As you can see, this is a log of products, so we can separate it into two logarithms (with the same base)


log(x^2)+log(y)

Now using the logarithm of a power to rewrite the log(x^2) we get:


2*log(x)+log(y)

User Cronoik
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