Determining bounds of a function

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Homework Statement



decide if f is bounded above or below, and if f takes on maximum or minimum value
f(x)= x^2 for x< or =a, a+2 for x>a
on (-a-1, a+1), assuming a>-1

Homework Equations



x^2 is continuous on R

The Attempt at a Solution



I have no idea where to start with this. I can constrain a+2 to (-1, a+1), but I don't know how that applies to the bounds of the entire function.
 
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ptolema said:

Homework Statement



decide if f is bounded above or below, and if f takes on maximum or minimum value
f(x)= x^2 for x< or =a, a+2 for x>a
on (-a-1, a+1), assuming a>-1

Homework Equations



x^2 is continuous on R

The Attempt at a Solution



I have no idea where to start with this. I can constrain a+2 to (-1, a+1), but I don't know how that applies to the bounds of the entire function.

Start by sketching a graph of this function. a is not given, so just pick some point on the positive x-axis and label it a. You might need to do this for several values of a, including at least one negative value.

Alternatively, you could choose a few specific values of a and graph this function for each of them, and see how the graphs are similar.

That's how I would start.
 
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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