Math Problem Statement

Solve the following logarithmic equations: a) log(2x) = -1, c) log(3x) = 2, e) log(x) = 3/2, g) log(x) + log(50) = log(100), i) log(x) = 1 + log(22 - x), k) 5log(2x) = 20.

Solution

It looks like you have provided an image with various logarithmic equations. Let's go through each one step by step and solve them.

a) log(2x)=1\log(2x) = -1

We can use the property of logarithms logb(a)=c\log_b(a) = c which means a=bca = b^c. In this case, the logarithm is in base 10 (common logarithm).

log(2x)=1    2x=101=0.1\log(2x) = -1 \implies 2x = 10^{-1} = 0.1 Solving for xx: x=0.12=0.05x = \frac{0.1}{2} = 0.05

c) log(3x)=2\log(3x) = 2

Again using the property of logarithms: log(3x)=2    3x=102=100\log(3x) = 2 \implies 3x = 10^2 = 100 Solving for xx: x=100333.33x = \frac{100}{3} \approx 33.33

e) logx=32\log x = \frac{3}{2}

Using the logarithmic property: logx=32    x=1032=103=100031.62\log x = \frac{3}{2} \implies x = 10^{\frac{3}{2}} = \sqrt{10^3} = \sqrt{1000} \approx 31.62

g) logx+log50=log100\log x + \log 50 = \log 100

Using the logarithmic property loga+logb=log(ab)\log a + \log b = \log(ab): log(x50)=log100    x50=100\log(x \cdot 50) = \log 100 \implies x \cdot 50 = 100 Solving for xx: x=10050=2x = \frac{100}{50} = 2

i) logx=1+log(22x)\log x = 1 + \log(22 - x)

We can isolate the logarithmic terms: logxlog(22x)=1    log(x22x)=1\log x - \log(22 - x) = 1 \implies \log\left(\frac{x}{22 - x}\right) = 1 This means: x22x=101=10\frac{x}{22 - x} = 10^1 = 10 Now, solving the equation: x=10(22x)    x=22010x    11x=220    x=20x = 10(22 - x) \implies x = 220 - 10x \implies 11x = 220 \implies x = 20

k) 5log(2x)=205\log(2x) = 20

Divide both sides by 5: log(2x)=4\log(2x) = 4 Now, use the logarithmic property: 2x=104=100002x = 10^4 = 10000 Solving for xx: x=100002=5000x = \frac{10000}{2} = 5000


Would you like more details or have any other questions about the steps? Here are some related questions that might help:

  1. What are some additional properties of logarithms that are useful for solving equations?
  2. How do you solve logarithmic equations with different bases (e.g., natural logarithms)?
  3. Can logarithmic equations ever have no solutions?
  4. What is the inverse relationship between exponential and logarithmic functions?
  5. How do you handle logarithms involving multiple terms on both sides of the equation?

Tip: Always remember that you can combine logarithms on the same side using properties like loga+logb=log(ab)\log a + \log b = \log(ab) and logalogb=log(ab)\log a - \log b = \log\left(\frac{a}{b}\right).

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Math Problem Analysis

Mathematical Concepts

Logarithmic Equations
Properties of Logarithms
Exponential Functions

Formulas

log_b(a) = c => a = b^c
log(a) + log(b) = log(ab)
log(a) - log(b) = log(a/b)

Theorems

Logarithmic Properties
Change of Base Property

Suitable Grade Level

Grades 9-11