Math Problem Statement

Show that log_{16}(xy) = (1/2)log_{4}(x) + (1/2)log_{4}(y)

Solution

The image shows the problem:

Show that: log16(xy)=12log4(x)+12log4(y)\log_{16}(xy) = \frac{1}{2}\log_{4}(x) + \frac{1}{2}\log_{4}(y)

Solution:

We begin by expressing the left-hand side, log16(xy)\log_{16}(xy), using properties of logarithms and simplifying it.

Step 1: Change of Base Formula

First, recall that: loga(b)=log(b)log(a)\log_{a}(b) = \frac{\log(b)}{\log(a)} Using this for log16(xy)\log_{16}(xy), we get: log16(xy)=log(xy)log(16)\log_{16}(xy) = \frac{\log(xy)}{\log(16)} But log(16)\log(16) can be simplified because 16=4216 = 4^2, so: log(16)=log(42)=2log(4)\log(16) = \log(4^2) = 2\log(4) Thus: log16(xy)=log(xy)2log(4)\log_{16}(xy) = \frac{\log(xy)}{2\log(4)}

Step 2: Apply Logarithmic Properties

Now, use the logarithmic property log(ab)=log(a)+log(b)\log(ab) = \log(a) + \log(b) to simplify log(xy)\log(xy): log(xy)=log(x)+log(y)\log(xy) = \log(x) + \log(y) Substitute this into the equation: log16(xy)=log(x)+log(y)2log(4)\log_{16}(xy) = \frac{\log(x) + \log(y)}{2\log(4)}

Step 3: Separate the Terms

This can now be written as: log16(xy)=12(log(x)log(4)+log(y)log(4))\log_{16}(xy) = \frac{1}{2}\left(\frac{\log(x)}{\log(4)} + \frac{\log(y)}{\log(4)}\right) Notice that log(x)log(4)=log4(x)\frac{\log(x)}{\log(4)} = \log_{4}(x) and log(y)log(4)=log4(y)\frac{\log(y)}{\log(4)} = \log_{4}(y), so: log16(xy)=12log4(x)+12log4(y)\log_{16}(xy) = \frac{1}{2}\log_{4}(x) + \frac{1}{2}\log_{4}(y)

Thus, we have shown that: log16(xy)=12log4(x)+12log4(y)\log_{16}(xy) = \frac{1}{2}\log_{4}(x) + \frac{1}{2}\log_{4}(y)

Would you like further details or explanations on any step?


Here are 5 related questions to explore:

  1. What is the change of base formula and how is it used in logarithmic equations?
  2. How can logarithmic properties help simplify expressions involving products?
  3. Can we generalize this result for different bases, such as logb(a)\log_b(a)?
  4. What happens if we change the base of logarithms from base 16 to base 2 in this problem?
  5. How can logarithms be applied to solve exponential equations?

Tip: Always remember that logarithms convert multiplication into addition, making it easier to handle complex expressions!

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Logarithms
Logarithmic Properties
Change of Base Formula

Formulas

log_a(b) = log(b) / log(a)
log(ab) = log(a) + log(b)
log(a^n) = n * log(a)

Theorems

Change of Base Theorem
Logarithmic Product Rule

Suitable Grade Level

High School - Grades 10-12