Editing 866: Compass and Straightedge

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{{w|Compass-and-straightedge construction|Compass and straightedge constructions}} are a class of problems in classical geometry. They take the form "Using only a compass and a straightedge, construct X", where X is a geometric figure such as a regular pentagon. The subject is typically covered in high school mathematics. Three such constructions ({{w|squaring the circle}}, {{w|Angle trisection|trisecting the angle}} and {{w|doubling the cube}}) remained unsolved for thousands of years before being shown impossible with the use of modern algebraic techniques.
 
{{w|Compass-and-straightedge construction|Compass and straightedge constructions}} are a class of problems in classical geometry. They take the form "Using only a compass and a straightedge, construct X", where X is a geometric figure such as a regular pentagon. The subject is typically covered in high school mathematics. Three such constructions ({{w|squaring the circle}}, {{w|Angle trisection|trisecting the angle}} and {{w|doubling the cube}}) remained unsolved for thousands of years before being shown impossible with the use of modern algebraic techniques.
  
The comic begins as if it were stating a problem in classical geometry but veers into an observation that no amount of technical knowledge can substitute for human companionship. An additional layer of humor is that [[Cueball]] is a stick figure so technically it is possible to create friends with a straightedge and a compass, a figure constructed like Cueball is. Yet two other layers are the reference to the "straight edge" subculture that believes that one can find fun, friends and partners without alcohol and drugs and the fact that it claims one can construct a awesome birthday party using only two means that together often fail to construct even simple geometrical objects.  
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The comic begins as if it were stating a problem in classical geometry but veers into an observation that no amount of technical knowledge can substitute for human companionship. An additional layer of humor is that [[Cueball]] is a stick figure so technically it is possible to create friends with a straightedge and a compass, a figure constructed like Cueball is.
  
 
{{w|Ferdinand von Lindemann}} was a German mathematician who showed in 1882 that pi is not a zero of any polynomial with rational coefficients, i.e. it is a transcendental number. Transcendental numbers cannot be constructed with straightedge and compass. This proves that {{w|squaring the circle}} (a problem where it is required to construct a square with the same area as a given circle) is impossible, being as the sides of the square would need to be √π times the radius of the circle, and pi is not constructible.
 
{{w|Ferdinand von Lindemann}} was a German mathematician who showed in 1882 that pi is not a zero of any polynomial with rational coefficients, i.e. it is a transcendental number. Transcendental numbers cannot be constructed with straightedge and compass. This proves that {{w|squaring the circle}} (a problem where it is required to construct a square with the same area as a given circle) is impossible, being as the sides of the square would need to be √π times the radius of the circle, and pi is not constructible.

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