N00b here and i got a question (logarithms)

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    Logarithms
In summary, to solve an exponential equation with base a algebraically, you can take the natural logarithm of both sides and use the rule ln xy = yln x to simplify the equation. The result can then be approximated to three decimal places by dividing ln 80 by 2ln 3.
  • #1
mathdummy
Okay.
"Solve the exponential equation with base a algebraically. Approximate the result to three decimal places."

3^2x=80

(fyi, the answer is ln80/2ln3 = 1.994)

Don't understand how to solve, please help!
 
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  • #2
As you already have the answer and you want to understand the question, I think it's okay to take you through it step-by-step:

32x = 80

take the natural logarithm of both sides:

ln 32x = ln 80

use the rule ln xy = yln x:

2xln 3 = ln 80

2x = ln 80/ln 3

x = ln 80/2ln 3
 
  • #3
Ah. Thanks alot! For future reference, how can i show the numbers being squared in the corner and small like you were able to
 

1. What are logarithms and why are they important?

Logarithms are mathematical functions that are used to solve exponential equations. They are important because they allow us to condense large numbers into more manageable values, and they have numerous applications in fields such as science, engineering, and finance.

2. What is the base of a logarithm and how does it affect the result?

The base of a logarithm is the number that is raised to a power in an exponential equation. The most commonly used bases are 10 and e (the natural logarithm). The base affects the result because it determines the relationship between the input and output values of the logarithmic function.

3. How do you solve logarithmic equations?

To solve a logarithmic equation, you can use the inverse property of logarithms which states that logb(x) = y if and only if by = x. This means that you can rewrite the logarithmic equation as an exponential equation and then solve for the unknown variable.

4. Can logarithms be negative?

Yes, logarithms can be negative. This occurs when the input of the logarithmic function is less than 1. In this case, the output will be a negative number.

5. What are some real-world applications of logarithms?

Logarithms have numerous real-world applications, including measuring the intensity of earthquakes and sound, calculating pH levels in chemistry, and modeling population growth and decay. They are also used in computer science and data compression algorithms.

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