Single equation involving two functions

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In summary, the conversation discusses a problem involving the function f(x) and its value at f(6). The equation 2f(x) + 3f(2010/x) = 5x is given and several attempts are made to solve for f(6) using substitution and algebraic methods. Ultimately, it is determined that f(6) can be solved for by setting x = 335 and solving the resulting system of equations.
  • #1
Freye
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0
1.
2f(x) +3f(2010/x) = 5x
f(6) = ?



2.
No relevant equations that I am aware of (although I suspect that the answer requires some law or equation that I am don't know)



3.
2f(x) = 3f(2010/x) = 5x
2f(x) = 5x - 3f(2010/x)
f(6) = 5(6)/2 - 3f(2010/6)/2
f(6) = 15 - 3f(335)/2

I suspect that this isn't even close to what I am supposed to do, but I haven't seen a question like this before, and I don't know of any way to solve it completely without another equation so I can use substitution for f(335).
 
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  • #2
Freye said:
1.
2f(x) +3f(2010/x) = 5x
f(6) = ?



2.
No relevant equations that I am aware of (although I suspect that the answer requires some law or equation that I am don't know)



3.
2f(x) = 3f(2010/x) = 5x
2f(x) = 5x - 3f(2010/x)
f(6) = 5(6)/2 - 3f(2010/6)/2
f(6) = 15 - 3f(335)/2

I suspect that this isn't even close to what I am supposed to do, but I haven't seen a question like this before, and I don't know of any way to solve it completely without another equation so I can use substitution for f(335).

Actually, I think you might be on the right track.
You have f(6) + (3/2) f(335) = 15

Now let x = 335 and plug that into your equation. That will give you two equations in the two unknowns f(6) and f(335), so you should be able to solve this system algebraically for f(6).
 
  • #3
Looks good to me...
 
  • #4
zgozvrm said:
Looks good to me...
If you're referring to Freye's answer, f(6) is in terms of f(335), which is not known, so f(6) isn't known, either.
 
  • #5
Thanks Mark, I actually thought of doing that at one point but for some reason I decided that I wasn't allowed to. I solved it and got the right answer! Thanks again
 

1. What is a single equation involving two functions?

A single equation involving two functions is an equation where one unknown variable is represented by two different functions. This means that the variable is dependent on both functions and the equation is used to find the value of the variable.

2. Why would I need to solve a single equation involving two functions?

Solving a single equation involving two functions can be useful in many fields of science, such as physics, chemistry, and biology. It allows us to find the relationship between two variables and make predictions or analyze data.

3. What are some common examples of single equations involving two functions?

Some common examples include the ideal gas law (PV = nRT), the Michaelis-Menten equation in biochemistry (V = Vmax[S]/(Km + [S])), and the quadratic formula (y = ax^2 + bx + c).

4. How do I solve a single equation involving two functions?

The key to solving a single equation involving two functions is to understand the relationship between the two functions and the unknown variable. You can use algebraic manipulation, substitution, or graphing to find the solution.

5. Can a single equation involving two functions have more than one solution?

Yes, a single equation involving two functions can have more than one solution. This means that there can be multiple values for the unknown variable that satisfy the equation. It is important to check your solution to make sure it is valid and makes sense in the context of the problem.

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