To find the value of Y when x=1, we can substitute x=1 into the equation Y=1/3x^3+x^2-3x:

Y = 1/3(1)^3 + (1)^2 - 3(1)

Y = 1/3 + 1 - 3

Y = 1/3 + 1 - 9/3

Y = 1/3 + 3/3 - 9/3

Y = (1 + 3 - 9)/3

Y = -5/3

Therefore, when x=1, Y=-5/3.