Find the sum of all real solutions

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In summary, the problem asks to find the sum of all real solutions for $x$ to the equation $\large (x^2+4x+6)^{{(x^2+4x+6)}^{(x^2+4x+6)}}=2014$. The solution involves finding a unique value of $y$ between $2$ and $3$ such that $y^{y^y} = 2014$, and then using the parabola function $y = x^2+4x+6$ to find two values of $x$ that satisfy the equation. The sum of these two values is $-4$. The problem may not be obvious at first, but it is enjoyable
  • #1
anemone
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Find the sum of all real solutions for $x$ to the equation $\large (x^2+4x+6)^{{(x^2+4x+6)}^{(x^2+4x+6)}}=2014$.

P.S. I know this doesn't count as a challenge(no matter how you slice it) because it's quite obvious and rather a very straightforward sort of problem but I'd like to share it because I enjoyed this problem much!
 
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  • #2
(sighs) You know I just got done telling someone on another Forum that you can't solve one of these in closed form...

-Dan
 
  • #3
Hey Dan,(Wave)

In this case, do you want me to PM you how I solved the problem while I let other members to have a little fun with this problem?
 
  • #4
anemone said:
Hey Dan,(Wave)

In this case, do you want me to PM you how I solved the problem while I let other members to have a little fun with this problem?
Sorry for the misinterpretation...I was a bit tired when I wrote that. I was't implying you were wrong, I was mentioning the irony that I had just told someone else it was impossible and your problem was implying that it could be done. My statement was badly worded, my apologies.

And I just read your PM...I was thinking the problem implied an explicit solution set for x, and that's not what the problem was actually about.

-Dan

Edit: Don't worry about PMing me your solution. I'll wait along with the rest. I don't have the slightest clue of how to do this...
 
  • #5
anemone said:
Find the sum of all real solutions for $x$ to the equation $\large (x^2+4x+6)^{{(x^2+4x+6)}^{(x^2+4x+6)}}=2014$.

P.S. I know this doesn't count as a challenge (no matter how you slice it) because it's quite obvious and rather a very straightforward sort of problem but I'd like to share it because I enjoyed this problem much!
I'm not sure that "it's quite obvious" – I might not have seen how to do it if I had not seen the comments about explicit solutions for $x$. But I agree that it's an enjoyable problem. Thanks for sharing it!
[sp]Let $f(y) = y^{y^y}$, for $y\geqslant1$. This is an increasing function, with $f(2) = 16 < 2014$ and $f(3) = 3^{27} > 2014$. So there is a unique value of $y$, between $2$ and $3$, with $f(y) = 2014.$

The function $y = x^2 + 4x + 6 = (x+2)^2 + 2$ represents a parabola with vertex at $(-2,2)$. It takes all values greater than $2$ exactly twice, and the sum of those two values is always $-4$. In particular, there are two values of $x$ such that $f(x^2 + 4x + 6) = 2014$, and their sum is $-4$.[/sp]
 
  • #6
Opalg said:
I'm not sure that "it's quite obvious" – I might not have seen how to do it if I had not seen the comments about explicit solutions for $x$. But I agree that it's an enjoyable problem. Thanks for sharing it!
[sp]Let $f(y) = y^{y^y}$, for $y\geqslant1$. This is an increasing function, with $f(2) = 16 < 2014$ and $f(3) = 3^{27} > 2014$. So there is a unique value of $y$, between $2$ and $3$, with $f(y) = 2014.$

The function $y = x^2 + 4x + 6 = (x+2)^2 + 2$ represents a parabola with vertex at $(-2,2)$. It takes all values greater than $2$ exactly twice, and the sum of those two values is always $-4$. In particular, there are two values of $x$ such that $f(x^2 + 4x + 6) = 2014$, and their sum is $-4$.[/sp]

Hi Opalg,:)

I'm so glad that you and many others liked this problem! I solved it pretty much like the way how you solved it and I do want to explain the very reason that led me to mention how I thought this problem is not difficult:

I was enlightened by the keyword "find the sum of the real roots"! That I knew immediately this problem isn't really asking us to solve for $x$s.

Thank you Opalg for participating!

I'll reply to my many other challenges the next day because it has been a long day for me and now, my eyes are strained, I'm exhausted and I can hardly think straight too! Goodbye and good night to everyone and MHB for now!
 

FAQ: Find the sum of all real solutions

What does "Find the sum of all real solutions" mean?

This phrase refers to finding the total value of all real numbers that can satisfy a given equation or problem. Real solutions are values that make the equation or problem true.

Why is finding the sum of all real solutions important?

Knowing the sum of all real solutions can help us understand the behavior of a system or equation, and can also provide insight into the nature of the problem being solved. It is an important step in finding the overall solution or understanding the problem better.

What is the difference between real solutions and complex solutions?

Real solutions are values that can be represented on the number line, while complex solutions involve imaginary numbers and cannot be represented on the number line. Real solutions are typically seen as more practical and useful in real-world applications.

How do you find the sum of all real solutions?

The specific method for finding the sum of all real solutions will depend on the problem or equation at hand. In general, you will need to solve the equation or problem to find the individual real solutions, and then add them together to find the total sum.

Can there be an infinite number of real solutions?

No, there cannot be an infinite number of real solutions. The number of real solutions will depend on the complexity and degree of the equation or problem being solved. In some cases, there may be no real solutions at all.

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