Power raised to a logarithm question

The answer is x. In summary, when solving for x in an equation such as 7^log(base: 7) 3 = x, we can use the inverse of the function to simplify and find the value of x. In this case, the inverse of 7x is log(base: 7) and plugging in the given value of 3, we get x=3.
  • #1
Coco12
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Homework Statement


Solve for x
7^log(base: 7) 3 = x

Homework Equations





The Attempt at a Solution


Ans is 3
Can someone explain to me how to solve for powers raised to a log like this one?
 
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  • #2
y = 10 ^ x then log y = x right ?

looking at log y = x then 10 ^ log y = 10 ^ x

but 10 ^ x is y so

10 ^ log y = y

now since 10 is the base follow the same logic with base 7
 
  • #3
in which grade are you??
 
  • #4
Coco12 said:
Can someone explain to me how to solve for powers raised to a log like this one?
7x is a function: for every real number x, 7x has a single, well-defined value. Denote this function as f(x): f(x)=7x. Rhetorical question: What's the inverse of this function? The answer is log base 7. Denote this as f-1(x)=log7x.

A non-rhetorical question: Given *any* function f(x) and its inverse f-1(x), what is f(f-1(x)) ?
 

FAQ: Power raised to a logarithm question

1. What is a power raised to a logarithm?

A power raised to a logarithm is an exponential equation in which the variable is the exponent and the base is the logarithm. For example, in the equation 3^log25, 3 is the base, log25 is the exponent, and the result is 5.

2. How do you solve a power raised to a logarithm equation?

To solve a power raised to a logarithm equation, you can use the logarithm power rule, which states that loga(x^y) = y*loga(x). This means that you can move the exponent down and multiply it by the logarithm of the base. For example, if you have the equation 2^log3(x) = 8, you can rewrite it as log3(x) = 3 and then solve for x by raising 3 to the power of 3, giving you x = 27.

3. Can a power raised to a logarithm equation have multiple solutions?

Yes, a power raised to a logarithm equation can have multiple solutions. This is because logarithms are not one-to-one functions, meaning that different inputs can produce the same output. When solving a power raised to a logarithm equation, you may need to check your answer to ensure that it is a valid solution.

4. How can I check my solution to a power raised to a logarithm equation?

To check your solution to a power raised to a logarithm equation, you can plug it back into the original equation and see if it satisfies the equation. For example, if your solution is x = 4, you can plug it into the equation 2^log3(x) = 8 to see if it is valid. You can also use a calculator to evaluate both sides of the equation and see if they are equal.

5. What are some real-life applications of power raised to a logarithm equations?

Power raised to a logarithm equations are commonly used in fields such as physics, chemistry, and engineering to model exponential growth and decay. They can also be used in finance to calculate compound interest and in computer science for algorithms and data compression. Additionally, they are used in biology to model population growth and in medicine to calculate drug dosages.

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