SOLUTION: "show that the maximum and minimum values of the function {{{f(theta) = 5cos(theta) + 12sin(theta)}}} are 13 and -13 respectively" plzz can anyone help me wd this...

Set that = 0 to find first coordinates of possible 
maximum and minimum points:





Divide both sides by 







Since tangent =  = , let y=±12, x=±5 













Now we substitute both possible values to find y-coordinates
of maximum and minimum points:

 and 



 becomes:





Now we choose both possible combinations of signs:

(1)  

(2)  


(1) gives the maximum value and (2) gives the minimum value
Edwin