Find the circumference of a circle whose diameter has endpoints at (2 , 1) and (4 , 5).
You need to remember that the endpoints of diameter lie on circle. Since you know coordinates of endpoints of diameter you may evaluate how long it is such that:`d=sqrt((2-4)^2+(1-5)^2)` .
`d=sqrt((-2)^2+(-4)^2) =gt d=sqrt(4+16) =gt d=sqrt20` `=gt d=sqrt(2^2*5)=gtd=2sqrt5`
Since the formula of circumference comprises the length of radius of circle, hence you may find the radius as half of diameter length.
You may evaluate circumference of circle such that:
Substituting `sqrt5` for r yields: circumference=`2sqrt5*pi` .
Hence, evaluating the circumference of circle yields circumference=`2sqrt5*pi ` units.
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