Proving Continuity of a Piecewise Function at x=1

chaoseverlasting
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Homework Statement


f(x) is a piecewise function defined as:

2(2e-e^x) x<1
3\pi x-4 x>=1

Discuss the continuity of f(x) at x=1.


Homework Equations





The Attempt at a Solution



Putting x=1 in the above function gives you 2e and 3\pi -4. They seem to be equal, but how do I prove it mathematically? I've missed something here, but don't know what.
 
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How many decimal places are you looking at? They aren't THAT close to being equal.
 
No idea. Is this thing continuous at x=1?
 
chaoseverlasting said:
No idea. Is this thing continuous at x=1?

It's a lot easier to show they aren't equal than that they are. Hint: they can't be equal, e and pi are algebraically independent. Just punch the things into calculator that shows more than two decimal places.
 
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Yeah, I did just that. The question has other parts which can only be solved if this thing was continuous. Nasty assumption.
 
2e and 3\pi-4 are definitely NOT equal!
 
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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