Solve Continuous Functions Equation: (f(x)^2)= x^2

Justabeginner
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Homework Statement


How many continuous functions f are there which satisfy the equation (f(x)^2) = x^2 for all x?

Homework Equations


The Attempt at a Solution


What method should I use to solve this? Is there a specific strategy involved besides plug and chug? Off the top of my head, I can only think of f(x)= x, but that's just one. Thank you.
 
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If you take square roots:
\sqrt{ a^2} = |a|
Is always a true statement regardless of whether a is positive or negative. So for your equation you get |f(x)| = |x|. Try working from there
 
Thank you so much for that derivation!
For this absolute function, there would be two possible values: -x and x.
There would only be two functions possible then I think?
I thought it would be more complicated, and involve log functions, etc.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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