A proof of an area as a set function

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Hi guys, recently, I am a freshmen majoring in Physics, recently using Apostle Calculus to self-study. However, I am having a hard time knowing whether if my proof is correct or not, since there isn't any solution.

Homework Statement


Prove that following set is measurable and has zero area: a set consisting of a single point.

The Attempt at a Solution



First, I have considered the Axiom of Choice of scale{Every rectangle R is in Measurable Set. If the edges of R have lengths h and k then a(R)=hk} to show that h and k both is zero therefore, a(Point)=0

but I couldn't convince myself that a point is an rectangle! So my former approach is not proper.

and I couldn't think up any other approaches so far.

would anyone be king enough to give me a few suggestions?

many thanks!
 
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Office_Shredder said:
Think about making really small rectangles around the point

Thank you very much indeed!

so here is my new approach, what would the problem be in my proof? :
let there be a point in a rectangle [itex]a^2[/itex]
[tex]\exists a\in R[/tex]
s.t. for all [itex]x\in R, 0<a<x[/itex]
[tex]\implies a^2=0[/tex]
[tex]\implies f(point)=0[/tex]