Questions: Suppose we want to combine the following into a single expression:
6 log3(x) + (1/0) log3(y) - 5 log3(z)
Transcript text: Suppose we want to combine the following into a single expression:
\[
6 \log _{3}(x)+\frac{1}{0} \log _{3}(y)-5 \log _{3}(z)
\]
Solution
Solution Steps
To combine the given logarithmic expressions into a single expression, we will use the power rule of logarithms, which states that alogb(c)=logb(ca). We will apply this rule to each term and then combine them using the properties of logarithms: the product rule logb(m)+logb(n)=logb(m⋅n) and the quotient rule logb(m)−logb(n)=logb(nm).
Solution Approach
Apply the power rule to each term:
6log3(x)=log3(x6)
01log3(y) is undefined due to division by zero, so this term cannot be combined.
−5log3(z)=log3(z−5)
Combine the valid terms using the product and quotient rules.
Step 1: Apply the Power Rule
We start with the expression:
6log3(x)+01log3(y)−5log3(z)
Applying the power rule alogb(c)=logb(ca) to the valid terms, we have:
6log3(x)=log3(x6)−5log3(z)=log3(z−5)
The term 01log3(y) is undefined and will be ignored.
Step 2: Combine the Logarithmic Terms
Now we can combine the valid logarithmic terms using the product and quotient rules:
log3(x6)−log3(z5)=log3(z5x6)
Step 3: Substitute Values
Substituting x=2 and z=3 into the expression:
log3(3526)
Calculating 26=64 and 35=243, we have:
log3(24364)
Step 4: Calculate the Logarithm
The numerical value of the logarithm is calculated as:
log3(24364)≈−1.2144
Final Answer
The combined logarithmic expression evaluates to approximately:
−1.2144