Show Proving Convexity of f(x)=||x|| Function

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The discussion focuses on proving the convexity of the function f(x) = ||x||, where ||x|| denotes the norm of vector x. The key approach involves utilizing the triangle inequality, which states that |tx + (1-t)y| ≤ |tx| + |(1-t)y| for any vectors x and y and any scalar t in the interval [0, 1]. This directly supports the definition of a convex function, confirming that f(x) is indeed convex.

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ahamdiheme
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How do i go about showing that if f(x)=\left\|x\left\| then f(x) is a convex function.


I'm thinking in the direction of the triangle inequality but don't know how to go about it. Any clues? thanks
 
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it just comes straight from definition of convex function

|tx+(1-t)y|\leq |tx| + |(1-t)y|
 
that is it, Thanks a lot!
 
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