M-23.J cm*/. / tins* 



23. Polar coordinates. If a fixed point in given in A 

 fixed directed str.u-l.t Int.- o/i. then the ponitx.u ..f any 

 point /' lie plane will bo fully determined by iu distance 







OP a p fmiii the fixed point, and by the angle which the 

 in.. "/' ikes with the fixed line. 



The fixed line OR is called the initial line or polar axis, the 

 fixed point the pole of the system, and the polar coordinates 

 of the point P are the radius vector p and tin- directional or 

 vectorial angle 0. The usual rule of signs applies to the 

 vectorial angle 0, and the radius \v. if meas- 



ure*! n along the terminal side of the angle 0. The 



j-.'int /' is designated l- tf ). 



>m \\li.i- a been said it is clear that one pair of 



polar coordinates (i.e., one value of p and one of 0) serve to 

 determine one, and but one, point On the 



li.md, if is restricted to values lying between and 

 2ir, thru any givm point may be designated by/ 

 pairs of coordinates. 





r 



/.'/.. the ]K)lar coordinates (8,60) determine the position 

 of the point . iiirh OP 8, and makes an angle of 60 



