Absolute Extrema of 2x - (x-2) on [0,1], [-3,4]

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    Absolute Extrema
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{} these brackets are going to represent the absolute value lines
the problem states
find the absolute extrema of the given function on each individual interval:
f(x)= {2x} - {x-2}
a) [0,1]
b) [-3, 4]

I know I need the derivative of the equation but it does not really give a good derivative since it would be f'(x)= 2 - {1}
 
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well, first what is {2x} equal to when x is from [0,1], als owhat is the value of {x-2}, do the same thing in the other interval!
 
You could also break the function up into the intervals (-\infty,0), [0,2), and [2,\infty) and write f as a piecewise function. Then, you can find the derivative on each of those open intervals (remember that the derivative won't necessarily be defined at 0 and 2).
 
how am i suppose to do tat
 
portillj said:
how am i suppose to do tat

Do u know how a piecewise defined function looks like? Well, to do that in this case you need to follow both my hints and also PingPong's hints!
 
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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