vi 



" 



TRANSFORMATION OF COORDINATES 



70. That the coordinates of a point which remains fr 



ne are changed by clianging the axes to which 

 fixed point is referred, is an immediate 

 consequence of the definition of coordi- 

 nates. 



It is also evident that the different 

 mates of any given point 

 rtesian and polar, for example) are 

 connected by definite relations if the ele- 

 ments of reference (the axes) are related in position. E.g. % 

 the point Q, when referred to the polar axis OX and the pole 

 0, has the coordinates (5, 80), but \\hen it is referred to 



the rectangular axes OX and 

 Kthe coordinates of this same 

 point are ( j V3, f ) ; and gen- 



^ > erally, if (/>, 6) be the co- 



^^\\ /' ordinates of a punt when 



V : <pl referred to OX and o. then 



0>cos0, p*\\\B) are its c 



when it is referred to the 



rectangular axes OX and 07. 



Again: while a rifrtw remains fixed in a pi 

 may often be gi niplified by a judicious change of 



