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 EXAMPLE 1
 
 Find the fundamental period of f (t) = sin kt1   For  k > 0
 
 Solution :  We know that,
             \      f (t) is periodic function with fundamental period 
  
 EXAMPLE 2
 
 Find whether f (t) = cos (5t + 4) is periodic?  If so, find its fundamental period.
 
 Solution :         Since cos t = cos (t + 
2p)
        \ f (t) is a periodic function and the fundamental period is 
2p/5. 
 EXAMPLE  3
 Find  a tangent function whose fundamental period is 9.
 
 Solution:          tan t = tan (t + p)
 
                          Let  f (t) = tan kt be the required function
 
                    \   f (t) = tan kt = tan (kt + p)
   EXAMPLE 4
 
 If sin x = 3/5 then what is the value of each of the following sin (x + 
6p), sin (x + 36000), 
 sin(x -10800).
 
 Solution:     sin (x + 6p) = sin (x + 2p),
 
                 sin (x + 36000) = sin (x + 10p) = sin (x + 
2p) and 
              
                 sin (x - 10800) = sin (x - 6p) = sin (x - 
2p)
 
        \    sin (x + 6p) = sin (x + 2p) = sin (x - 
2p) = 3/5 since the function is periodic with          period  
2p.          
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