Convex function on closed interval?

csc2iffy
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Homework Statement


Let K be the closed interval [0,1] and consider the function f(x)=x^2. Is f convex? Is f linear?

help please :/ i don't even know how to set this up to check, our teacher didn't even get to this in class yet!


Homework Equations





The Attempt at a Solution

 
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csc2iffy said:

Homework Statement


Let K be the closed interval [0,1] and consider the function f(x)=x^2. Is f convex? Is f linear?

help please :/ i don't even know how to set this up to check, our teacher didn't even get to this in class yet!


Homework Equations





The Attempt at a Solution


What is the definition of a linear function? Does your f(x) satisfy that? What is the definition of a convex function? Does that apply to f(x)? If your teacher has not covered that material yet, is it nevertheless in your textbook? If not, you can use Google, or go to the library.

RGV
 
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