Answer :

To rewrite the logarithmic expression [tex]\(\ln \left(\frac{e^3 r}{y^2}\right)\)[/tex] as the sum or difference of logs, we can use the properties of logarithms. Let's go through the steps:

1. Apply the logarithm of a quotient property:
The property states that [tex]\(\ln \left(\frac{A}{B}\right) = \ln A - \ln B\)[/tex]. Here, [tex]\(A = e^3 r\)[/tex] and [tex]\(B = y^2\)[/tex]. So,

[tex]\[ \ln \left(\frac{e^3 r}{y^2}\right) = \ln (e^3 r) - \ln (y^2). \][/tex]

2. Apply the logarithm of a product property:
The property states that [tex]\(\ln (AB) = \ln A + \ln B\)[/tex]. For the term [tex]\(\ln (e^3 r)\)[/tex], we can split it into:

[tex]\[ \ln (e^3 r) = \ln (e^3) + \ln (r). \][/tex]

3. Simplify the logarithm of an exponential:
The property states that [tex]\(\ln (e^k) = k\)[/tex]. Hence, for the term [tex]\(\ln (e^3)\)[/tex], we get:

[tex]\[ \ln (e^3) = 3. \][/tex]

4. Combine all the results:
Now we can combine everything back together:

[tex]\[ \ln (e^3 r) - \ln (y^2) = [\ln (e^3) + \ln (r)] - \ln (y^2). \][/tex]

We already simplified [tex]\(\ln (e^3)\)[/tex] to 3, so:

[tex]\[ \ln (e^3 r) - \ln (y^2) = [3 + \ln (r)] - \ln (y^2). \][/tex]

5. Apply the logarithm of a power property:
The property states that [tex]\(\ln (A^k) = k \ln (A)\)[/tex]. For the term [tex]\(\ln (y^2)\)[/tex], we get:

[tex]\[ \ln (y^2) = 2 \ln (y). \][/tex]

6. Final combination:
Substituting back, we get:

[tex]\[ \ln \left(\frac{e^3 r}{y^2}\right) = 3 + \ln (r) - 2 \ln (y). \][/tex]

Hence, the logarithmic expression [tex]\(\ln \left(\frac{e^3 r}{y^2}\right)\)[/tex] can be written as:

[tex]\[ \ln \left(\frac{e^3 r}{y^2}\right) = \ln (r) - 2 \ln (y) + 3. \][/tex]