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bob012345 reacted to kuruman's post in the thread Undergrad Descartes’ Geometry of Square Roots with
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If you define segments ##b##, ##h## and ##a## using the drawing on the right, it has been shown here that... -
bob012345 replied to the thread Undergrad Descartes’ Geometry of Square Roots.For Descartes, yes. In post #1 I mentioned this was a variation of Descartes’ original problem. His case is when ##a## is taken as... -
bob012345 reacted to kuruman's post in the thread Undergrad Descartes’ Geometry of Square Roots with
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I agree wholeheartedly, however one needs to be careful. Writing ##b+1## mixes apples and oranges. Having reached ##h^2=ab##, I would... -
bob012345 replied to the thread Undergrad Descartes’ Geometry of Square Roots.In my mind all these quantities are lengths representing pure numbers. We can say ##3=\sqrt{9}## without saying ##9## has different... -
bob012345 replied to the thread Undergrad Descartes’ Geometry of Square Roots.I think we need to remember we are talking about geometric constructions here. We can define a line segment as 1 unit then construct... -
bob012345 reacted to kuruman's post in the thread Undergrad Descartes’ Geometry of Square Roots with
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I had an overnight revelation about this. It should resonate with any person who has been sensitized to the importance of units. Here it... -
bob012345 replied to the thread How good is Brian Cox as a science communicator?.Regarding the use of the word computer, I think he’s basically correct. Digital devices have exploded everywhere but we don’t call them... -
bob012345 reacted to neilparker62's post in the thread Undergrad Descartes’ Geometry of Square Roots with
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Let D be the point where the perpendicular meets AB. Then: $$\triangle ADC \sim \triangle CDB \implies \frac{h}{b}=\frac{a}{h} $$ -
bob012345 reacted to neilparker62's post in the thread Undergrad Descartes’ Geometry of Square Roots with
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Very tactfully put by Descartes! Nicolaus Copernicus in a header page of De Revolutionibus Orbium Coelestium writes somewhat more... -
bob012345 reacted to PhDeezNutz's post in the thread Undergrad Descartes’ Geometry of Square Roots with
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in polar coordinates a circle whose center is on the x-axis is given by the graph ##r=2R \cos \theta## ##r = 2R \cos \theta =... -
bob012345 reacted to kuruman's post in the thread Undergrad Descartes’ Geometry of Square Roots with
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I would think that Descartes used similar triangles to finish this purely geometric that can be constructed with ruler and straight edge... -
bob012345 replied to the thread Undergrad Descartes’ Geometry of Square Roots.I think inventing the geometric construction was the big accomplishment. We are left merely with the pleasure of showing that it works... -
bob012345 reacted to kuruman's post in the thread Undergrad Descartes’ Geometry of Square Roots with
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Yes, I had that one also and that is why I labeled sides ##h_1## and ##h_2##. However, I dropped it after seeing @renormalize's, more... -
bob012345 replied to the thread Undergrad Descartes’ Geometry of Square Roots.From the book I gather Descartes starts with line segment we call ##b## then extends it by ##a## which he takes as 1. His goal is to... -
bob012345 reacted to Ibix's post in the thread Undergrad Descartes’ Geometry of Square Roots with
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@kuruman's construction can also be solved using Pythagoras on the three right angled triangles: $$\begin{eqnarray} h_1^2&=&b^2+h^2\\...
