Math Problem Statement

Find x if log(x^2) = 2log(8) - 2 and log(x^2) = 2log(4) - 2.

Solution

The problem appears to involve finding xx in two different equations involving logarithms. The task is split into two variants:

Variant 1:

logx2=2log82\log x^2 = 2 \log 8 - 2

Solution for Variant 1:

  1. Start with the given equation: logx2=2log82\log x^2 = 2 \log 8 - 2

  2. Use the property of logarithms that logx2=2logx\log x^2 = 2 \log x, so the equation becomes: 2logx=2log822 \log x = 2 \log 8 - 2

  3. Factor out 2 from the right-hand side: 2logx=2(log81)2 \log x = 2(\log 8 - 1)

  4. Divide both sides by 2: logx=log81\log x = \log 8 - 1

  5. Since log8=log(23)=3log2\log 8 = \log (2^3) = 3 \log 2, we get: logx=3log21\log x = 3 \log 2 - 1

  6. Let’s assume a logarithm base 10, and find the value of xx.

Variant 2:

logx2=2log42\log x^2 = 2 \log 4 - 2

Solution for Variant 2:

  1. Start with the given equation: logx2=2log42\log x^2 = 2 \log 4 - 2

  2. Use the same property: logx2=2logx\log x^2 = 2 \log x, so: 2logx=2log422 \log x = 2 \log 4 - 2

  3. Simplify by factoring out 2: 2logx=2(log41)2 \log x = 2(\log 4 - 1)

  4. Divide by 2: logx=log41\log x = \log 4 - 1

  5. Since log4=log(22)=2log2\log 4 = \log (2^2) = 2 \log 2, we get: logx=2log21\log x = 2 \log 2 - 1

  6. Solve for xx.

Let me know if you need the detailed solutions or have any further questions!

Five Questions to Explore:

  1. What are the properties of logarithms that are useful in solving equations like these?
  2. How would the equations change if the base of the logarithm was not 10?
  3. How can we use a calculator to find the numerical value of xx?
  4. What are some common logarithmic equations and their applications?
  5. Can we solve these equations using natural logarithms (base ee) instead?

Tip:

Remember that logarithmic equations often require the use of properties like the power rule (logab=bloga\log a^b = b \log a) and the product rule (log(ab)=loga+logb\log(ab) = \log a + \log b). Familiarizing yourself with these can make solving problems quicker and more intuitive!

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Math Problem Analysis

Mathematical Concepts

Logarithms
Exponential Equations
Logarithmic Properties

Formulas

log(x^2) = 2log(x)
log(ab) = log(a) + log(b)
log(a^b) = b*log(a)

Theorems

Logarithmic Properties
Power Rule
Product Rule

Suitable Grade Level

Grades 10-12