Regular Pentagon Coordinates Calculation

Extract

[...] Regular Pentagon being a regular pentagon, we have: As the points and are on the unit circle, we have the coordinates of and : Calculons : From where: According to the above, the abscissa of is . And as is on the unity circle, we have: According to the above, the abscissa of is . And as is on the unity circle, we have: In summarizing the previous questions, we deduce that: Check the previous results on the calculator. [...]