v 



APPENDIX A 

 Circular Measure The Radian 



The rail* ular angle subtended by an arc 



; equal in length tq the radius of its circle as shown in 

 the figure. The circle has a radius of r units and 

 " the radian is subtended by an arc whose length is r 

 units. 



* As the circumference of a circle is 2rr units, there 

 must be 2ir or 6.283 radians in> 360. Therefore 1 

 radian equals 360/2*- = 57.30. It follows that 

 180 = IT radian- 



Angular velocity is often expressed in radians per second, and the an 

 symbol is a> (omega). In every revolution a rotating quantity completes 

 2r radians. If the rotating quantity makes n revolutions per second, its 

 angular velocity w = 2irn radians per second. 



APPENDIX B 

 Trigonometry Simple Functions 



opposite side 



1. I he sine (sm) of an angle 



hypotenuse 



adjacent side 



2. I he cosine (cos) of an angle = i- 



hypotenuse 



_ opposite side 



13. 



Ratio of ndc< in :i right isoe- 



fnaniile 



/I 

 gree right 



16. rifl It - Z - COB A - cos (90 - B), since A - 90 - B 



16. .OH B - I - sin (90 -B) 



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