402 

 (19) 



(20) 



(21) 



PRACTICAL MATHEMATICS 



(22) The value of y, a periodic function of t, is here given for 

 twelve equidistant values of t covering the whole period. Express 

 y in a Fourier's series : 13-602, 18-468, 20-671, 20-182, 17-820, 

 14-346, 10-130, 5-612, 1-877, 0-486, 2-500, 7-506. (B. of E., 1910.) 



(23) A sliding piece has a periodic motion. Its distance x 

 from a point in its path is measured at twenty-four equal intervals 

 into which the whole periodic time is divided. Express x in a 

 Fourier's series : 16-04, 16-74, 16-66, 15-86, 14-68, 13-42, 12-26, 

 11-16, 9-98, 8-76, 7-60, 6-68, 5-96, 5-34, 4-68, 4-14, 3-98, 4-50, 5-74, 

 7-46, 9-36, 11-24, 13-06, 14-70. (B. of E., 1906.) 



