# Questions tagged [circles]

For questions concerning circles. A circle is the locus of points in a plane that are at a fixed distance from a fixed point.

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### Scale intersecting circles fixed at pivots so that they have only one point in common

Given two points, A and B; Given two circles, having 2 points in common, I1 and I2: one circle at center C1, with radius r1, with the point A on to it and another circle at center C2, with radius r2, ...
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### Finding mean and variance of the circumference of a circle.

I was tasked with solving the following problem. Suppose that we draw a circle whose radius $R$ is uniformly distributed on the interval $(0, 1)$. Find the mean and variance of the circumference of ...
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### Connected rates of change with Area and feta (Further math question)

Question about the rate of change in delta A Hi can anyone explain to me how to do section b of this question? This question is about arcs length, area of sectors and connected rates of change.
It is a well known result that all compact $1$-dimensional smooth manifolds are diffeomorphic to a circle. I'm wondering if the result still holds if we replace the word diffeomorphic with isometric. ...