minta bantuannya dong yang pinter mm,tolong jawab nomor 10 dan 11

10) x = t^2 + 1
x pada saat 2 s = 2^2 + 1 = 5
x pada saat 3 s = 3^2 + 1 = 10
v rata2 = (x2-x1)/(t2-t1)
=(10-5)/(3-2) = 5 m/s

11) x(t) = 4t^2
100 = 4t^2
t^2 = 25
t = 5

v = dx/dt
= 8t
= 8.5 = 40 m/s