Evaluate \[$\log_6 \left(\frac{1}{12}\right)\$\].

by ADMIN 50 views

=====================================================

Introduction


In mathematics, logarithms are a fundamental concept that plays a crucial role in various mathematical operations, including algebra, geometry, and calculus. The logarithm of a number is the exponent to which another fixed number, the base, must be raised to produce that number. In this article, we will evaluate the logarithm log6(112)\log_6 \left(\frac{1}{12}\right), which involves understanding the properties of logarithms and applying them to simplify the expression.

Understanding Logarithms


A logarithm is the inverse operation of exponentiation. It is a mathematical function that takes a number as input and returns the exponent to which a base number must be raised to produce that number. For example, if we have the equation 23=82^3 = 8, then the logarithm of 8 with base 2 is 3, denoted as log28=3\log_2 8 = 3. This means that 2 raised to the power of 3 equals 8.

Properties of Logarithms


Logarithms have several properties that are essential in evaluating expressions like log6(112)\log_6 \left(\frac{1}{12}\right). Some of the key properties of logarithms include:

  • Product Rule: logb(xy)=logbx+logby\log_b (xy) = \log_b x + \log_b y
  • Quotient Rule: logb(xy)=logbxlogby\log_b \left(\frac{x}{y}\right) = \log_b x - \log_b y
  • Power Rule: logb(xy)=ylogbx\log_b (x^y) = y \log_b x

Evaluating log6(112)\log_6 \left(\frac{1}{12}\right)


To evaluate log6(112)\log_6 \left(\frac{1}{12}\right), we can use the properties of logarithms mentioned above. We can start by expressing 112\frac{1}{12} as a product of prime factors.

112=1223\frac{1}{12} = \frac{1}{2^2 \cdot 3}

Step 1: Apply the Quotient Rule


Using the quotient rule, we can rewrite log6(112)\log_6 \left(\frac{1}{12}\right) as:

log6(112)=log6(1223)\log_6 \left(\frac{1}{12}\right) = \log_6 \left(\frac{1}{2^2 \cdot 3}\right)

Step 2: Apply the Product Rule


Now, we can apply the product rule to rewrite the expression as:

log6(1223)=log6(122)log63\log_6 \left(\frac{1}{2^2 \cdot 3}\right) = \log_6 \left(\frac{1}{2^2}\right) - \log_6 3

Step 3: Simplify the Expression


We can simplify the expression further by applying the power rule:

log6(122)log63=2log62log63\log_6 \left(\frac{1}{2^2}\right) - \log_6 3 = -2 \log_6 2 - \log_6 3

Step 4: Evaluate the Logarithms


To evaluate the logarithms, we need to find the values of log62\log_6 2 and log63\log_6 3. We can use the change of base formula to rewrite these logarithms in terms of common logarithms:

log62=log2log6\log_6 2 = \frac{\log 2}{\log 6}

log63=log3log6\log_6 3 = \frac{\log 3}{\log 6}

Step 5: Substitute the Values


Substituting the values of log62\log_6 2 and log63\log_6 3 into the expression, we get:

2log62log63=2(log2log6)(log3log6)-2 \log_6 2 - \log_6 3 = -2 \left(\frac{\log 2}{\log 6}\right) - \left(\frac{\log 3}{\log 6}\right)

Step 6: Simplify the Expression


Simplifying the expression further, we get:

2(log2log6)(log3log6)=2log2log3log6-2 \left(\frac{\log 2}{\log 6}\right) - \left(\frac{\log 3}{\log 6}\right) = \frac{-2 \log 2 - \log 3}{\log 6}

Step 7: Evaluate the Expression


To evaluate the expression, we need to find the values of log2\log 2, log3\log 3, and log6\log 6. We can use a calculator to find these values:

log20.301\log 2 \approx 0.301

log30.477\log 3 \approx 0.477

log60.778\log 6 \approx 0.778

Step 8: Substitute the Values


Substituting the values of log2\log 2, log3\log 3, and log6\log 6 into the expression, we get:

2log2log3log62(0.301)0.4770.778\frac{-2 \log 2 - \log 3}{\log 6} \approx \frac{-2(0.301) - 0.477}{0.778}

Step 9: Simplify the Expression


Simplifying the expression further, we get:

2(0.301)0.4770.7780.6020.4770.778\frac{-2(0.301) - 0.477}{0.778} \approx \frac{-0.602 - 0.477}{0.778}

Step 10: Evaluate the Expression


Evaluating the expression, we get:

0.6020.4770.7781.0790.778\frac{-0.602 - 0.477}{0.778} \approx \frac{-1.079}{0.778}

Step 11: Simplify the Expression


Simplifying the expression further, we get:

1.0790.7781.39\frac{-1.079}{0.778} \approx -1.39

The final answer is 1.39\boxed{-1.39}.

=============================

Frequently Asked Questions


Q: What is a logarithm?


A: A logarithm is the inverse operation of exponentiation. It is a mathematical function that takes a number as input and returns the exponent to which a base number must be raised to produce that number.

Q: What are the properties of logarithms?


A: The properties of logarithms include:

  • Product Rule: logb(xy)=logbx+logby\log_b (xy) = \log_b x + \log_b y
  • Quotient Rule: logb(xy)=logbxlogby\log_b \left(\frac{x}{y}\right) = \log_b x - \log_b y
  • Power Rule: logb(xy)=ylogbx\log_b (x^y) = y \log_b x

Q: How do I evaluate a logarithm?


A: To evaluate a logarithm, you can use the properties of logarithms mentioned above. You can start by expressing the number as a product of prime factors and then apply the product and quotient rules to simplify the expression.

Q: What is the change of base formula?


A: The change of base formula is a formula that allows you to rewrite a logarithm in terms of a common logarithm. It is given by:

logbx=logxlogb\log_b x = \frac{\log x}{\log b}

Q: How do I use the change of base formula?


A: To use the change of base formula, you can substitute the values of logx\log x and logb\log b into the formula and simplify the expression.

Q: What is the value of log6(112)\log_6 \left(\frac{1}{12}\right)?


A: The value of log6(112)\log_6 \left(\frac{1}{12}\right) is approximately -1.39.

Q: How do I evaluate log6(112)\log_6 \left(\frac{1}{12}\right)?


A: To evaluate log6(112)\log_6 \left(\frac{1}{12}\right), you can use the properties of logarithms mentioned above. You can start by expressing 112\frac{1}{12} as a product of prime factors and then apply the product and quotient rules to simplify the expression.

Q: What are some common logarithms?


A: Some common logarithms include:

  • log2x\log_2 x
  • log3x\log_3 x
  • log4x\log_4 x
  • log5x\log_5 x
  • log6x\log_6 x

Q: How do I use a calculator to evaluate a logarithm?


A: To use a calculator to evaluate a logarithm, you can enter the expression into the calculator and press the "log" button. The calculator will then display the value of the logarithm.

Q: What are some real-world applications of logarithms?


A: Logarithms have many real-world applications, including:

  • Finance: Logarithms are used to calculate interest rates and investment returns.
  • Science: Logarithms are used to calculate the pH of a solution and the concentration of a substance.
  • Engineering: Logarithms are used to calculate the gain of an amplifier and the frequency response of a circuit.
  • Computer Science: Logarithms are used to calculate the time complexity of an algorithm and the space complexity of a data structure.

Conclusion


In conclusion, logarithms are a fundamental concept in mathematics that have many real-world applications. By understanding the properties of logarithms and how to evaluate them, you can solve a wide range of problems in finance, science, engineering, and computer science.