Finding the power using logarithm

In summary, the conversation discusses a problem where the equation 3*10^x = 1.73*10^14 needs to be solved. The individual attempted to solve it using the equation lga^x = xlga, but received incorrect answers. After some discussion and clarification, they found the correct solution by taking the logarithm of the expression. The conversation also includes a question about the significance of the expressions (5.767*10)^{13} and 5.767*(10^{13}).
  • #1
disregardthat
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Actually, I am trying to use what I have learned on school to something else

Homework Statement



3*10^x = 1.73*10^14

Homework Equations



lga^x = xlga

The Attempt at a Solution



10^x = (1.73 * 10^14)/3
10^x = 5.767 * 10^13
xlg10 = 13lg(57.67)

x=13lg(57.67)
x=22.89

:\

3 * 10^22.89 = 1.73 * 10^14 is certainly not correct..
What am I doing wrong?

I tried this too:
x=5.767 * 13lg(10)
x=5.767 * 13
x = 74.971

And that is even more incorrect!
 
Last edited:
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  • #2
Jarle said:
Actually, I am trying to use what I have learned on school to something else

Homework Statement



3*10^x = 1.73*10^14

Homework Equations



lga^x = xlga

The Attempt at a Solution



10^x = (1.73 * 10^14)/3
10^x = 5.767 * 10^13
xlg10 = 13lg(57.67) HOW DID YOU GET YOUR RIGHT-HAND SIDE HERE?

Answer my question, please!
 
  • #3
i know that if a=b, then lga = lgb
and lga^x=xlga

then i just took the ^13 on the other hand of lg.5.767*10, an made that 13lg5.767*10) and that is 13lg57.67

But if that is incorrect, I tryed it the other way underneath. How am I supposed to get the right answer?

EDIT: I found out the right answer now.

I took the lg(0.576*10^14) and that became 13.76

and 3*10^13,76 is approximately 1.73*10^14
 
Last edited:
  • #4
Questions:

1. Do you see any difference between the expressions:
[itex](5.767*10)^{13}[/itex] and [itex]5.767*(10^{13})[/itex]?

2. Do you see any relevance of 1. to the issue at hand?
 
  • #5
I saw the difference, and I got my answer correct.

What do you mean by the number 2. I didn't uderstand :confused:
 
  • #6
He was asking you if you saw why that difference was important!
 
  • #7
I saw the difference afterwards :)
 

FAQ: Finding the power using logarithm

What is logarithm?

Logarithm is a mathematical function that represents the power to which a base number must be raised in order to get a given value. It is the inverse function of exponentiation.

How is logarithm used to find power?

Logarithm is used to find power by using the formula logb(x) = y, where b is the base, x is the given value, and y is the power. By rearranging the formula, we can find the power (y) by taking the logarithm of x with base b.

What is the purpose of using logarithm to find power?

The purpose of using logarithm to find power is to simplify complex mathematical calculations. It allows us to convert multiplication and division problems into simpler addition and subtraction problems, making calculations easier and more efficient.

What are the common bases used in logarithm?

The most commonly used bases in logarithm are 10, e (Euler's number), and 2. These bases are used because of their mathematical significance and convenience in calculations.

How is logarithm used in real-life applications?

Logarithm is used in various real-life applications such as measuring the intensity of earthquakes, calculating the pH scale, determining sound levels, and analyzing population growth. It is also used in finance and economics to calculate compound interest and depreciation.

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