Constructing a Regular Pentagon within given Circle By Using Ruler and Compass 

Yes ,you are absolutely aright

Jazziano

Seriously what the heck🤔

You musn't say that to hurt him or her

@@joelsanni1696 Musn't say what? I was just pointing out the differences between the tool being used, and that there's a better option. (35+ years as a professional draftsman)

Wow i has very invisible

Funny you sound say this. I tried something of this scale initially, and it worked out. I figured larger would be better, as there would be fewer "rounding errors", but I've encountered the same issue as you. This doesn't scale up. Which means there is "flaw" which is hidden with a 50mm circle, but is revealed with a larger circle, or something else is wrong. Notice at the end of this video the 5th line segment doesn't "exactly" line up with the starting point. That could be an indication this method doesn't yield a perfect 72 degree angle. I've never seen a technical description of why this construction works. It could be this is close to a pentagon, but not exact. This is still better than free-hand drawing a pentagon. :)

Oo

Very hard method

It can be shown that it does work using geometry, algebra, and law of cosines. It is not an approximate method. Errors in construction are of course possible.

The last step, marking off the circle with the points, is the source of error. Stepping around the circle in one direction will introduce an error, as seen. The length used in stepping is a tiny bit off, so the marks are slanted in that direction. Step around the circle, using the same starting point each time, but a clock-wise pass and an anti-clockwise pass. Each point on the circle now has two 'steps', instead of one. Clock-wise steps drift one way, anti-clockwise steps drift the opposite way, at the same rate. The intersections of the step-marks is the correct central angle for the pentagon. Draw a line from the center of the circle through the step intersection, and where that line crosses the circle, make your dot. Connect the dots, Pentagon!

Selamat datang😊

Yeah

Your school probably uses a different method or you're just dumb

Pause button.

omg,,sorry for inconvenience..

thanks.....hee heee heee......

Racist

RACIST I:( not cool

RAJESH shrestha Color does not matter His color can be black but he is smarter than you See his efforts that he is making to make us understand

Good music too