A particle moves according to the law X =a cos (pi t)/2 . The distance covered by it in the time interval between t = 0 to 1 = 3 sec is

A particle moves according to the law X =a cos (pi t)/2 . The distance

1.	A particle moves according to the law X =a cos (pi t)/2 . The distance covered by it in the time interval between t = 0 to 1 = 3 sec is
Answer» ` 2A ` `3 a` `4 a` `a` ANSWER :B