Re: Plane Geometry Basics

Hey keosan22.

Hint: Try forming an equilateral triangle using the three points of each circle at its tangent point with the large circle and then calculate the center of this triangle to get the centre of the big circle and then its radius as a function of a.

You will have to prove that the triangle is equilateral, and depending on what knowledge you have, I would suggest using a symmetry argument of some sort.

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Re: Plane Geometry Basics

Re: Plane Geometry Basics

Thank you both for your replies.

I am grateful that people still answer when asked

I stopped studying for a long time...many reasons...poverty in the Philippines is one of them

Things tend to slip after a few years. I am humbled by my inability to answer this question...and mortified (I am really gonna need a lot of help to graduate)

My fellow students and instructors have quite a busy schedule so I couldn't get around to asking them

Gonna try to solve the ones I can on my own...when I stumble across something I can't I'll post it here and hopefully someone replies

Thank you for your time

(Bow)

Re: Plane Geometry Basics

Thanks for such that help me also in understanding the plane geometry basics.. This post clear all my doubt regarding this topic... Now i am very much satisfy with my concept...

Thanks again...

Re: Plane Geometry Basics

this may help

draw an equilateral triangle and its three medians

small circle radius a

medians meet in centroid of triangle which is center of large circle

use properties of 30-60-90 triangle to find the distance between the centroid and a triangle vertex

radius of large circle is that distance plus a