What is the relation between Degrees and Radians?

A Circle of Radius r has a Circumference of 2πr,a Circle of radius 1 unit has circumference 2π.When ɵ is a complete rotation,P travels the Circumference of an unit circle completely.

If ɵ is a complete rotation then ɵ =2πradian.onthe other hand we already know that one complete rotation is 360^o,Consequently,360^o=2π radians or 180^o=π radian.It Follows that 1^o=π/180 radian and 180^o/π=1 radian.Therefore 1^o=0.01746  approximately radian and 1 radian=180^ox7/22=57^o16' approximately.
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