What are Direct and Inverse Images in Mathematics?

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Homework Statement



The problem is attached and my attempt for direct image is also attached.
I seek help in inverse image.

Homework Equations





The Attempt at a Solution

 

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You did part (a) correctly!

Part (b):
If h = g \circ f, then h^{-1} = f^{-1} \circ g^{-1}.
Look at the boundaries of G. They will give you the boundaries of its inverse image. This isn't ALWAYS the case, but our function here is pretty simple so it will work out well.
 
Based on your suggestions...
 

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mhmm! and a nice self-assuring way to check that you "almost definitely" got it right is the fact that f(\{x : -2 \le x \le 0\}) = G. I say "almost definitely" because it could happen that you luck out and it works even though your answer's wrong...but let's not worry about that haha. you got it right!
 
It turns out, I am not too dumb, yay! (Thank you for your patience, Raskolnikov.)
 
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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