대답:
# "t = 7에있는 물체의 속도는 v (7) = 3.78"#
설명:
# (dp (t)) / (dt) = v (t) #
# (dp (t)) / (dt) = 3 + pi / 8 * sin (π / 8t) + 0 #
#v (t) = 3 + pi / 8 * sin (pi / 8t) #
# v (7) = 3 + pi / 8 + sin (pi / 8 * 7) #
#sin ((7pi) / 8) = 0.38268343 #
#v (7) = 3 + pi / 8 + 0.38268343 #
# v (7) = pi / 8 + 3.38268343 #
# pi / 8 = 0.39269908 #
# v (7) = 0.39269908 + 3.38268343 = 3.7753825 #
#v (7) = 3.78 #